media: ov2680: Annotate the per mode register setting lists

Annotate the per mode register setting lists.

This is a preparation patch for moving to calculating the per mode
settings, allowing to set any mode through cropping.

The annotations make it easier to see which registers are mode
dependent and which are fixed.

Acked-by: Rui Miguel Silva <rmfrfs@gmail.com>
Reviewed-by: Daniel Scally <dan.scally@ideasonboard.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>