media: rkisp1: Support devices lacking self path

media: rkisp1: Support devices lacking self path

Some versions of the ISP supported by the rkisp1 driver, such as the ISP
in the i.MX8MP, lack the self path. Support those ISP versions by adding
a self path feature flag, and massage the rest of the driver to support
the lack of a self path.

Signed-off-by: Paul Elder <paul.elder@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Tested-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Tested-by: Adam Ford <aford173@gmail.com>
Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>