nativesdk-icecc-toolchain: Use TARGET_PREFIX in post-relocate
The icecc setup for the SDK was broken in multilib configurations now
that each multilib environment runs the post-relocate scripts
separately. Including $TARGET_PREFIX in the icecc shim path and in the
toolchain environment name prevents the various multilib setups from
conflicting.
[YOCTO #13128]
Signed-off-by: Joshua Watt <JPEWhacker@gmail.com> Signed-off-by: Ross Burton <ross.burton@intel.com>
