Return -EINVAL if invalid bus-type is detected while parsing endpoints.

Fixes: 26c1126c ("media: v4l: fwnode: Use media bus type for bus parser selection")
Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>