Patch merged into coreboot/master: crosstool: add EXPAT as a dependency on the gdb build.

the following patch was just integrated into master:
commit fb944f4270d787e2e705b46698d9f9851ea8a20e
Author: Ronald G. Minnich 
Date:   Sat Feb 27 04:06:42 2016 +0000

crosstool: add EXPAT as a dependency on the gdb build.

qemu-power8 wants to tell about itself with XML, and so
    we need to build gdb with EXPAT so it can understand XML.

Change-Id: I460e27f883956ed5d54e6070916e2682ee0f7a1b
    Signed-off-by: Ronald G. Minnich 
    Reviewed-on: https://review.coreboot.org/13846
    Tested-by: build bot (Jenkins)
    Reviewed-by: Stefan Reinauer 
    Reviewed-by: Martin Roth

See https://review.coreboot.org/13846 for details.

-gerrit