Clobbering output is only really useful when debugging the script.
Since we're only using short options, let's save 'c' for something
more important.
Change-Id: If87a70fdc0cd006818d1736c40f9984dfec663a9
Signed-off-by: David Hendricks <dhendrix@chromium.org>
Reviewed-on: http://review.coreboot.org/4047
Tested-by: build bot (Jenkins)
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>