[SYCL][ESIMD][EMU] Atomicity control for ESIMD_EMULATOR plug-in

[dongkyunahn-intel]

Atomicity control in ESIMD_EMULATOR plug-in implementation uses dynamic allocation for global locks at module construction.

Comment by @lsatanov : #4748 (comment)

This type of implementation was imported from level_zero and it is noted that there is memory leak in level_zero plug-in implementation. ESIMD_EMULATOR implementation has same comments for corresponding implementation.

llvm/sycl/plugins/level_zero/pi_level_zero.cpp

Line 394 in e6d0547

static sycl::detail::SpinLock *PiPlatformsCacheMutex =

llvm/sycl/plugins/level_zero/pi_level_zero.cpp

Line 7591 in e6d0547

bool LeakFound = false;

@romanovvlad suggested relocating global variable (including locks) allocation to piInitialize and deallocation to piTearDown

#4748 (comment)

@dongkyunahn-intel will create a PR designated for this issue as soon as on-going changes and fixes are applied in ESIMD_EMULATOR plug-in implementation.