Patch merged into coreboot/master: xcompile: Add XGCCPATH to clang compiler

the following patch was just integrated into master:
commit 51d4de818dfd92ab7a17c473fd4c5b6bd32837f8
Author: Martin Roth 
Date:   Tue Jan 5 14:30:22 2016 -0700

xcompile: Add XGCCPATH to clang compiler

The XGCCPATH prefix is on all the other tools and compilers,
    so add it to clang as well, so it can be found correctly.

Change-Id: Ibc250a81433f37bbb0555d32605aebe3a68aaf40
    Signed-off-by: Martin Roth 
    Reviewed-on: https://review.coreboot.org/12839
    Tested-by: build bot (Jenkins)
    Reviewed-by: Patrick Georgi

See https://review.coreboot.org/12839 for details.

-gerrit