ARM: shmobile: bockw: add USB, VIN pin descriptions to DT

Adds pin control info for USB host and video-in devices.

Signed-off-by: Ulrich Hecht <ulrich.hecht+renesas@gmail.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>