The format enumeration list is shared between CSI-2 and DVP modes.
This lead to the enumeration of unsupported format variants in both
modes.

Separate the list of DVP and CSI-2 formats and create helpers to access
the correct one.
Signed-off-by: NJacopo Mondi <jacopo@jmondi.org>
Reviewed-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NSakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@kernel.org>