[media] soc-camera: Pass the physical device to the power operation

There will be no soc_camera_device instance with a soc-camera device is
used with a non soc-camera host, so we won't be able to pass the
soc_camera_device fake platform device to board code. Pass the physical
device instead.

The argument is currently not used by any board file so this is safe.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>