[media] dibusb: fix sparse warnings

drivers/media/usb/dvb-usb/dibusb-common.c:261:40: warning: restricted __le16 degrades to integer
drivers/media/usb/dvb-usb/dibusb-common.c:262:52: warning: restricted __le16 degrades to integer
drivers/media/usb/dvb-usb/dibusb-common.c:300:40: warning: restricted __le16 degrades to integer
drivers/media/usb/dvb-usb/dibusb-common.c:301:44: warning: restricted __le16 degrades to integer
drivers/media/usb/dvb-usb/dibusb-common.c:313:47: warning: restricted __le16 degrades to integer
drivers/media/usb/dvb-usb/dibusb-common.c:314:47: warning: restricted __le16 degrades to integer

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>