media: rcar-vin: Add RCAR_GEN4 model value

media: rcar-vin: Add RCAR_GEN4 model value

Currently Gen4 VINs are marked as RCAN_GEN3 models. Add a new enum
value, RCAR_GEN4, and use it for Gen4 VINs. No functional changes in
this patch.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen+renesas@ideasonboard.com>
Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Tested-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Link: https://lore.kernel.org/r/20250424-rcar-fix-raw-v2-1-f6afca378124@ideasonboard.com
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>