[media] au0828: properly handle stream on/off state

The STREAM_ON state is used by s_format callback,
but the driver never sets it.

Fix it. This will also be needed in order to handle
suspend/resume ops.
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>

drivers/media/usb/au0828/au0828-video.c

@@ -159,6 +159,7 @@ static void au0828_irq_callback(struct urb *urb)
 		au0828_isocdbg("urb resubmit failed (error=%i)\n",
 			       urb->status);
 	}
+	dev->stream_state = STREAM_ON;
 }
 
 /*
@@ -198,6 +199,8 @@ static void au0828_uninit_isoc(struct au0828_dev *dev)
 	dev->isoc_ctl.urb = NULL;
 	dev->isoc_ctl.transfer_buffer = NULL;
 	dev->isoc_ctl.num_bufs = 0;
+
+	dev->stream_state = STREAM_OFF;
 }
 
 /*