media: i2c: ov772x: Parse endpoint properties

Parse endpoint properties using v4l2_fwnode_endpoint_alloc_parse()
to determine the bus type and store it in the driver structure.

Set bus_type to V4L2_MBUS_PARALLEL as it's the only supported one

Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Jacopo Mondi <jacopo+renesas@jmondi.org>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>