Patch merged into coreboot/master: d1f840b toolchain.inc: Check toolchain is installed before running it

the following patch was just integrated into master:
commit d1f840be86a8af750c7b7a44907e842d7a28a061
Author: Marc Jones 
Date:   Thu Jan 22 16:18:49 2015 +0800

toolchain.inc: Check toolchain is installed before running it

Toolchain.inc fails with strange shell errors if the CC_$(stage)
    doesn't expands correctly. The cause is that the ARCH_SUPPORTED
    doesn't have the required toolchain for the stage.

Change-Id: Id284ce281546b2b1b166f2b13d087bc6b114440e
    Signed-off-by: Marc Jones 
    Reviewed-on: http://review.coreboot.org/8257
    Tested-by: build bot (Jenkins)
    Reviewed-by: Furquan Shaikh 
    Reviewed-by: Paul Menzel

See http://review.coreboot.org/8257 for details.

-gerrit