media: dt-bindings: media: renesas-ceu: Add more endpoint properties

As the v4l2-fwnode framework now allows specifying defaults configurations,
expand the description of the optional endpoint properties for the CEU
interface to better explain which are their defaults values.

Signed-off-by: Jacopo Mondi <jacopo+renesas@jmondi.org>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

Documentation/devicetree/bindings/media/renesas,ceu.txt

@@ -26,6 +26,10 @@ the above mentioned "video-interfaces.txt" file are supported.
   default is active high.
 - vsync-active: See [1] for description. If property is not present,
   default is active high.
+- bus-width: See [1] for description. Accepted values are '8' and '16'.
+  If property is not present, default is '8'.
+- field-even-active: See [1] for description. If property is not present,
+  an even field is identified by a logic 0 (active-low signal).
 
 Example: