When adding support for NV12 it was overlooked that the pixel format is
only supported on some VIN channels. Fix this by adding a check to only
accept NV12 on the supported channels 0, 1, 4, 5, 8, 9, 12 and 13.
Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>