V4L/DVB (7334): usb video: add a device link to usbvideo devices, else hal will ignore them

Signed-off-by: Pascal Terjan <pterjan@mandriva.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>