media: i2c: imx290: set bus_type before calling v4l2_fwnode_endpoint_alloc_parse()
The bus_type field of v4l2_fwnode_endpoint structure passed as the argument
to v4l2_fwnode_endpoint_alloc_parse() function must be initiaized.
Set it to V4L2_MBUS_CSI2_DPHY, and check for -ENXIO which is returned
when the requested media bus type doesn't match the fwnode.
Also remove v4l2_fwnode_endpoint field from struct imx290 as it is only
needed in the probe function: use the local variable for this purpose.