media: v4l: fwnode: Add definitions for CSI-2 D-PHY, parallel and Bt.656 busses

Add definitions corresponding to DT bindings to the CSI-2 D-PHY, parallel
and Bt.656 busses.

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Tested-by: Steve Longerbeam <steve_longerbeam@mentor.com>
Tested-by: Jacopo Mondi <jacopo+renesas@jmondi.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>