Patch merged into coreboot/master: cbfstool: Silence LZ4 -Wsign-compare warnings

the following patch was just integrated into master:
commit 17cb0370a70ccfc2301b7974bf38d44c7271afea
Author: Julius Werner 
Date:   Mon Feb 22 15:30:37 2016 -0800

cbfstool: Silence LZ4 -Wsign-compare warnings

It seems that the exact behavior of -Wsign-compare changes between GCC
    versions... some of them like the commonlib/lz4_wrapper.c code, and some
    don't. Since we don't have a well-defined HOSTCC toolchain this slipped
    through pre-commit testing. Explicitly silence the warning to ensure
    cbfstool still builds on all systems.

Change-Id: I43f951301d3f14ce34dadbe58e885b82d21d6353
    Signed-off-by: Julius Werner 
    Reviewed-on: https://review.coreboot.org/13769
    Tested-by: build bot (Jenkins)
    Reviewed-by: Aaron Durbin

See https://review.coreboot.org/13769 for details.

-gerrit