[media] cx23885: uninitialized variable in cx23885_av_work_handler()

The "handled" variable could be uninitialized if the
interrupt_service_routine() call back hasn't been implimented or if it
has been implemented but doesn't initialize "handled" to zero at the
start.  For example, adv76xx_isr() only sets "handled" to true.

Fixes: 44b153ca639f ('[media] m5mols: Add ISO sensitivity controls')

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

drivers/media/pci/cx23885/cx23885-av.c

@@ -24,7 +24,7 @@ void cx23885_av_work_handler(struct work_struct *work)
 {
 	struct cx23885_dev *dev =
 			   container_of(work, struct cx23885_dev, cx25840_work);
-	bool handled;
+	bool handled = false;
 
 	v4l2_subdev_call(dev->sd_cx25840, core, interrupt_service_routine,
 			 PCI_MSK_AV_CORE, &handled);