Patch merged into coreboot/master: build system: don't run xcompile or git for %clean/%config targets

the following patch was just integrated into master:
commit 0ffef882d8357b1e14e983829e0a26415ab43b48
Author: Patrick Georgi 
Date:   Thu Jan 19 23:20:14 2017 +0100

build system: don't run xcompile or git for %clean/%config targets

It takes a long time for no gain: We don't need to update the
    submodules, we don't need to fetch the revision, we don't need to find
    the compilers, when all we want to do is to manipulate the .config file
    or clean the build directory.

Change-Id: Ie1bd446a0d49a81e3cccdb56fe2c43ffd83b6c98
    Signed-off-by: Patrick Georgi 
    Reviewed-on: https://review.coreboot.org/18182
    Tested-by: build bot (Jenkins)
    Reviewed-by: Paul Menzel 
    Reviewed-by: Martin Roth

See https://review.coreboot.org/18182 for details.

-gerrit