yabel: explicitly cast values to match printk expectations

Change-Id: Id2230ecd800b138b6ccbbac318e71c9edf076c75
Signed-off-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
Reviewed-on: http://review.coreboot.org/12116
Tested-by: build bot (Jenkins)
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Patrick Georgi <pgeorgi@google.com>
1 file changed