In case of error clear the wire buffer and put in idle mode

[fabik111]

Problem

This PR addresses the problem that if any action fails, every other requests that might be completed successfully fail because the Wire data buffer is not cleared and the ECCX08 is not put into idle mode.

This PR covers also the problem highlighted in #70

How to reproduce the problem

Run this sketch changing the slotID with one that is empty:

#include <Arduino_SecureElement.h>
#include <utility/SElementArduinoCloudDeviceId.h>
#include <utility/SElementArduinoCloudCertificate.h>
#include <utility/SElementArduinoCloudJWT.h>
SecureElement secureElement;
int slotID = 4;

void setup() {
  // put your setup code here, to run once:
  Serial.begin(9600);
  while(!Serial);
    // Init the secure element
  if(!secureElement.begin()) {
    Serial.println("not begin");
    while(1);
  }

  if (!secureElement.locked()) {
    if (!secureElement.writeConfiguration()) {
          Serial.println("not write config");
    while(1);
    }

    if (!secureElement.lock()) {
                Serial.println("not locked");
    while(1);
    }
  }
  byte publicKey[64];
 
  if(!secureElement.generatePublicKey(slotID, publicKey)){
    
    Serial.println("slot 4 empty");
    if(!secureElement.generatePrivateKey(slotID, publicKey)){
      Serial.println("Error: private key generation failed");
    }else{
      Serial.println("generation prvk completed");
      for(uint8_t i=0; i<sizeof(publicKey); i++){
        Serial.print(publicKey[i], HEX);
        Serial.print(" ");
      }
    
    }
  } else{
    Serial.println("slot 4 not empty");
  }
}

void loop() {
  // put your main code here, to run repeatedly:

}

The expected output is:

slot 4 empty
generation prvk completed
[the public key]

The current output:

slot 4 empty
Error: private key generation failed

[github-actions]

Memory usage change @ df1480b

Board	flash	%	RAM for global variables	%
arduino:mbed:envie_m7	🔺 0 - +64	0.0 - +0.01	0 - 0	0.0 - 0.0
arduino:mbed_giga:giga	🔺 0 - +64	0.0 - 0.0	0 - 0	0.0 - 0.0
arduino:mbed_nano:nanorp2040connect	🔺 +32 - +32	0.0 - 0.0	0 - 0	0.0 - 0.0
arduino:mbed_opta:opta	🔺 0 - +64	0.0 - 0.0	0 - 0	0.0 - 0.0
arduino:megaavr:uno2018	🔺 +66 - +66	+0.14 - +0.14	0 - 0	0.0 - 0.0
arduino:samd:mkr1000	🔺 +32 - +32	+0.01 - +0.01	0 - 0	0.0 - 0.0
arduino:samd:mkrwan1300	🔺 +32 - +32	+0.01 - +0.01	0 - 0	0.0 - 0.0
arduino:samd:mkrgsm1400	🔺 +32 - +32	+0.01 - +0.01	0 - 0	0.0 - 0.0
arduino:samd:mkrnb1500	🔺 +32 - +32	+0.01 - +0.01	0 - 0	0.0 - 0.0
arduino:samd:mkrvidor4000	🔺 +32 - +32	+0.01 - +0.01	0 - 0	0.0 - 0.0
arduino:samd:mkrwan1310	🔺 +32 - +32	+0.01 - +0.01	0 - 0	0.0 - 0.0
arduino:samd:mkrwifi1010	🔺 +32 - +32	+0.01 - +0.01	0 - 0	0.0 - 0.0
arduino:samd:nano_33_iot	🔺 +32 - +32	+0.01 - +0.01	0 - 0	0.0 - 0.0

Click for full report table

Board	examples/ECCX08Counter flash	%	examples/ECCX08Counter RAM for global variables	%	examples/ECCX08HMAC flash	%	examples/ECCX08HMAC RAM for global variables	%	examples/ECCX08RandomNumber flash	%	examples/ECCX08RandomNumber RAM for global variables	%	examples/ECCX08Signing flash	%	examples/ECCX08Signing RAM for global variables	%	examples/Tools/ECCX08CSR flash	%	examples/Tools/ECCX08CSR RAM for global variables	%	examples/Tools/ECCX08JWSPublicKey flash	%	examples/Tools/ECCX08JWSPublicKey RAM for global variables	%	examples/Tools/ECCX08SelfSignedCert flash	%	examples/Tools/ECCX08SelfSignedCert RAM for global variables	%
arduino:mbed:envie_m7	64	0.01	0	0.0	64	0.01	0	0.0	64	0.01	0	0.0	0	0.0	0	0.0	64	0.01	0	0.0	0	0.0	0	0.0	0	0.0	0	0.0
arduino:mbed_giga:giga	0	0.0	0	0.0	64	0.0	0	0.0	0	0.0	0	0.0	64	0.0	0	0.0	0	0.0	0	0.0	64	0.0	0	0.0	64	0.0	0	0.0
arduino:mbed_nano:nanorp2040connect	32	0.0	0	0.0	32	0.0	0	0.0	32	0.0	0	0.0	32	0.0	0	0.0	32	0.0	0	0.0	32	0.0	0	0.0	32	0.0	0	0.0
arduino:mbed_opta:opta	0	0.0	0	0.0	0	0.0	0	0.0	0	0.0	0	0.0	64	0.0	0	0.0	0	0.0	0	0.0	64	0.0	0	0.0	64	0.0	0	0.0
arduino:megaavr:uno2018	66	0.14	0	0.0	66	0.14	0	0.0	66	0.14	0	0.0	66	0.14	0	0.0	66	0.14	0	0.0	66	0.14	0	0.0	66	0.14	0	0.0
arduino:samd:mkr1000	32	0.01	0	0.0	32	0.01	0	0.0	32	0.01	0	0.0	32	0.01	0	0.0	32	0.01	0	0.0	32	0.01	0	0.0	32	0.01	0	0.0
arduino:samd:mkrwan1300	32	0.01	0	0.0	32	0.01	0	0.0	32	0.01	0	0.0	32	0.01	0	0.0	32	0.01	0	0.0	32	0.01	0	0.0	32	0.01	0	0.0
arduino:samd:mkrgsm1400	32	0.01	0	0.0	32	0.01	0	0.0	32	0.01	0	0.0	32	0.01	0	0.0	32	0.01	0	0.0	32	0.01	0	0.0	32	0.01	0	0.0
arduino:samd:mkrnb1500	32	0.01	0	0.0	32	0.01	0	0.0	32	0.01	0	0.0	32	0.01	0	0.0	32	0.01	0	0.0	32	0.01	0	0.0	32	0.01	0	0.0
arduino:samd:mkrvidor4000	32	0.01	0	0.0	32	0.01	0	0.0	32	0.01	0	0.0	32	0.01	0	0.0	32	0.01	0	0.0	32	0.01	0	0.0	32	0.01	0	0.0
arduino:samd:mkrwan1310	32	0.01	0	0.0	32	0.01	0	0.0	32	0.01	0	0.0	32	0.01	0	0.0	32	0.01	0	0.0	32	0.01	0	0.0	32	0.01	0	0.0
arduino:samd:mkrwifi1010	32	0.01	0	0.0	32	0.01	0	0.0	32	0.01	0	0.0	32	0.01	0	0.0	32	0.01	0	0.0	32	0.01	0	0.0	32	0.01	0	0.0
arduino:samd:nano_33_iot	32	0.01	0	0.0	32	0.01	0	0.0	32	0.01	0	0.0	32	0.01	0	0.0	32	0.01	0	0.0	32	0.01	0	0.0	32	0.01	0	0.0

Click for full report CSV

Board,examples/ECCX08Counter<br>flash,%,examples/ECCX08Counter<br>RAM for global variables,%,examples/ECCX08HMAC<br>flash,%,examples/ECCX08HMAC<br>RAM for global variables,%,examples/ECCX08RandomNumber<br>flash,%,examples/ECCX08RandomNumber<br>RAM for global variables,%,examples/ECCX08Signing<br>flash,%,examples/ECCX08Signing<br>RAM for global variables,%,examples/Tools/ECCX08CSR<br>flash,%,examples/Tools/ECCX08CSR<br>RAM for global variables,%,examples/Tools/ECCX08JWSPublicKey<br>flash,%,examples/Tools/ECCX08JWSPublicKey<br>RAM for global variables,%,examples/Tools/ECCX08SelfSignedCert<br>flash,%,examples/Tools/ECCX08SelfSignedCert<br>RAM for global variables,%
arduino:mbed:envie_m7,64,0.01,0,0.0,64,0.01,0,0.0,64,0.01,0,0.0,0,0.0,0,0.0,64,0.01,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0
arduino:mbed_giga:giga,0,0.0,0,0.0,64,0.0,0,0.0,0,0.0,0,0.0,64,0.0,0,0.0,0,0.0,0,0.0,64,0.0,0,0.0,64,0.0,0,0.0
arduino:mbed_nano:nanorp2040connect,32,0.0,0,0.0,32,0.0,0,0.0,32,0.0,0,0.0,32,0.0,0,0.0,32,0.0,0,0.0,32,0.0,0,0.0,32,0.0,0,0.0
arduino:mbed_opta:opta,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,0,0.0,64,0.0,0,0.0,0,0.0,0,0.0,64,0.0,0,0.0,64,0.0,0,0.0
arduino:megaavr:uno2018,66,0.14,0,0.0,66,0.14,0,0.0,66,0.14,0,0.0,66,0.14,0,0.0,66,0.14,0,0.0,66,0.14,0,0.0,66,0.14,0,0.0
arduino:samd:mkr1000,32,0.01,0,0.0,32,0.01,0,0.0,32,0.01,0,0.0,32,0.01,0,0.0,32,0.01,0,0.0,32,0.01,0,0.0,32,0.01,0,0.0
arduino:samd:mkrwan1300,32,0.01,0,0.0,32,0.01,0,0.0,32,0.01,0,0.0,32,0.01,0,0.0,32,0.01,0,0.0,32,0.01,0,0.0,32,0.01,0,0.0
arduino:samd:mkrgsm1400,32,0.01,0,0.0,32,0.01,0,0.0,32,0.01,0,0.0,32,0.01,0,0.0,32,0.01,0,0.0,32,0.01,0,0.0,32,0.01,0,0.0
arduino:samd:mkrnb1500,32,0.01,0,0.0,32,0.01,0,0.0,32,0.01,0,0.0,32,0.01,0,0.0,32,0.01,0,0.0,32,0.01,0,0.0,32,0.01,0,0.0
arduino:samd:mkrvidor4000,32,0.01,0,0.0,32,0.01,0,0.0,32,0.01,0,0.0,32,0.01,0,0.0,32,0.01,0,0.0,32,0.01,0,0.0,32,0.01,0,0.0
arduino:samd:mkrwan1310,32,0.01,0,0.0,32,0.01,0,0.0,32,0.01,0,0.0,32,0.01,0,0.0,32,0.01,0,0.0,32,0.01,0,0.0,32,0.01,0,0.0
arduino:samd:mkrwifi1010,32,0.01,0,0.0,32,0.01,0,0.0,32,0.01,0,0.0,32,0.01,0,0.0,32,0.01,0,0.0,32,0.01,0,0.0,32,0.01,0,0.0
arduino:samd:nano_33_iot,32,0.01,0,0.0,32,0.01,0,0.0,32,0.01,0,0.0,32,0.01,0,0.0,32,0.01,0,0.0,32,0.01,0,0.0,32,0.01,0,0.0