drm/bridge: ti-tfp410: Set connector type based on DT connector node

The TI TFP410 is a DVI encoder, not a full HDMI encoder. Its output can
be routed to a DVI-D connector, even if in many cases embedded systems
will use an HDMI connector to carry the DVI signals.

Instead of hardcoding the connector type to HDMI, retrieve the connector
type from its DT node.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Reviewed-by: Jyri Sarha <jsarha@ti.com>
Tested-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>