[media] coda: Do not use __cancel_delayed_work()

commit 136b5721 (workqueue: deprecate __cancel_delayed_work()) made
__cancel_delayed_work deprecated. Use cancel_delayed_work instead and get rid of
the following warning:
drivers/media/platform/coda.c:1543: warning: '__cancel_delayed_work' is deprecated (declared at include/linux/workqueue.h:437)

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Javier Martin <javier.martin@vista-silicon.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>