[media] tw68: remove deprecated IRQF_DISABLED

See include/linux/interrupt.h:
"This flag is a NOOP and scheduled to be removed"

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>