Support device caps

Use the V4L2 video device caps instead of the global caps when
available.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Support additional dpcm compressed bayer formats.

Signed-off-by: Sakari Ailus <sakari.ailus@iki.fi>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>