some messages take 4 bytes, but only fill 3 bytes....
this patch makes sure that whatever we send to the SCU is zeroed first
Signed-off-by: NArjan van de Ven <arjan@linux.intel.com>
Signed-off-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NMatthew Garrett <mjg@redhat.com>