Memory-to-memory devices should copy various parts of
struct v4l2_buffer from the output buffer to the capture buffer.

Add a helper function that does that to simplify the driver code.
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Reviewed-by: Paul Kocialkowski <paul.kocialkowski@bootlin.com>
Reviewed-by: Alexandre Courbot <acourbot@chromium.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>