[media] siano: split debugfs code into a separate file

To avoid mixing two different things at the same place, move the
debugfs code into a separate file.

Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/usb/siano/smsusb.c

@@ -412,6 +412,8 @@ static int smsusb_init_device(struct usb_interface *intf, int board_id)
 
 	smscore_set_board_id(dev->coredev, board_id);
 
+	dev->coredev->is_usb_device = true;
+
 	/* initialize urbs */
 	for (i = 0; i < MAX_URBS; i++) {
 		dev->surbs[i].dev = dev;