[media] marvell-ccic: drop support for PIX_FMT_422P

I cannot get this format to work, the colors keep coming out wrong.
Since this has never worked I just drop support for this.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Acked-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>