V4L/DVB (12244): em28xx: adjust vinmode/vinctl based on the stream input format

Depending on the video input format, vinmode/vinctl needs adjustments.
For TV, this is not relevant, since the supported decoders output data
at the same format. However, webcam sensors may have different formats,
so, this needs to be adjusted based on the device.

Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>