Building rust with --enable-rpath fails

[bkoropoff]

rustc: x86_64-unknown-linux-gnu/stage0/lib/rustlib/x86_64-unknown-linux-gnu/lib/libcore
error: unknown codegen option: `rpath`
make: *** [x86_64-unknown-linux-gnu/stage0/lib/rustlib/x86_64-unknown-linux-gnu/lib/stamp.core] Error 101

[alexcrichton]

Oh dear, good catch! This just needs a new snapshot, and one is currently building.