media: amphion: encoder add support for contiguous planes

encoder add support for contiguous formats NV12

Signed-off-by: Ming Qian <ming.qian@nxp.com>
Reviewed-by: Tommaso Merciai <tommaso.merciai@amarulasolutions.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>