[coreboot] Patch merged into coreboot/master: 475d42a cbfstool: Add `-Werror` to make all warnings into errors

the following patch was just integrated into master:
commit 475d42a16c0a9ce3946c1ac2b3d20c32feec4fec
Author: Paul Menzel 
Date:   Mon Feb 18 11:56:13 2013 +0100

cbfstool: Add `-Werror` to make all warnings into errors

Ensure that no changes with warnings are committed. Although using
    `-Werror` is debatable [1][2].

[1] http://blog.flameeyes.eu/2009/02/future-proof-your-code-dont-use-werror
    [2] http://gcc.gnu.org/onlinedocs/gcc/Warning-Options.html

Change-Id: I402f2d82dd4087d8a575b0a85305a02ef04bb537
    Signed-off-by: Paul Menzel 
    Reviewed-on: http://review.coreboot.org/2441
    Tested-by: build bot (Jenkins)
    Reviewed-by: Patrick Georgi

Reviewed-By: Patrick Georgi  at Mon Feb 18 12:10:35 2013, giving +2
See http://review.coreboot.org/2441 for details.

-gerrit