[media] davinci: vpif: add support for clipping on output data

add hardware clipping support for VPIF output data. This
is needed as it is possible that the external encoder
might get confused between the FF or 00 which are a part
of the data and that of the SAV or EAV codes.

Signed-off-by: Manjunath Hadli <manjunath.hadli@ti.com>
Signed-off-by: Lad, Prabhakar <prabhakar.lad@ti.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>