[media] dvb-usb-v2: add support for the media controller at USB driver
Create a struct media_device and add it to the dvb adapter.
Please notice that the tuner is not mapped yet by the dvb core.
[mchehab@osg.samsung.com: use config option MEDIA_CONTROLLER_DVB due to a rebase] Signed-off-by: Rafael Lourenço de Lima Chehab <chehabrafael@gmail.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>