If rc_validate_filter() is called for CEC or XMP, then we would read
beyond the end of the array.
Suggested-by: NHans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: NSean Young <sean@mess.org>
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>