Allow XGCCPATH to be set on the make command line.

The xgcc toolchain may be moved by the user and passed in on the commandline. Updates the Makefile and the xcompile script.

Change-Id: I05797b2cabce39bdd7868c2515f30d34043fc8cc
Signed-off-by: Marc Jones <marcj303@gmail.com>
Reviewed-on: http://review.coreboot.org/318
Tested-by: build bot (Jenkins)
Reviewed-by: Patrick Georgi <patrick@georgi-clan.de>
2 files changed