[coreboot-gerrit] Patch merged into coreboot/master: build system: replace files on UPDATE_IMAGE

the following patch was just integrated into master:
commit 89b4abdf80ae64374f378058bc3f2f5484a7f977
Author: Patrick Georgi 
Date:   Tue Dec 1 18:34:42 2015 +0100

build system: replace files on UPDATE_IMAGE

So far the build system only added files starting with CBFS_PREFIX/ in
    the UPDATE_IMAGE configuration, but there are a number of files that
    exist in the global namespace (eg. config, revision, but also
    cmos_layout.bin).

Now, existing files are removed if necessary.

Change-Id: I977ff85fe18115c84268103be72e91ca854e62a4
    Signed-off-by: Patrick Georgi 
    Reviewed-on: https://review.coreboot.org/12581
    Reviewed-by: Timothy Pearson 
    Tested-by: build bot (Jenkins)
    Reviewed-by: Paul Menzel 
    Tested-by: Raptor Engineering Automated Test Stand 
    Tested-by: BSI firmware lab

See https://review.coreboot.org/12581 for details.

-gerrit