media: rkisp1: Implement ENUM_FRAMESIZES

Implement VIDIOC_ENUM_FRAMESIZES for the rkisp1 capture devices.

Signed-off-by: Paul Elder <paul.elder@ideasonboard.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Dafna Hirschfeld <dafna@fastmail.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>