[media] cx25821: Drop Freeing of Workqueue

Workqueues shouldn't be freed. destroy_workqueue should be used instead.
destroy_workqueue safely destroys a workqueue and ensures that all pending
work items are done before destroying the workqueue.
Signed-off-by: Bhaktipriya Shridhar <bhaktipriya96@gmail.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

drivers/media/pci/cx25821/cx25821-audio-upstream.c

@@ -242,7 +242,7 @@ void cx25821_stop_upstream_audio(struct cx25821_dev *dev)
 	dev->_audioframe_count = 0;
 	dev->_audiofile_status = END_OF_FILE;
 
-	kfree(dev->_irq_audio_queues);
+	destroy_workqueue(dev->_irq_audio_queues);
 	dev->_irq_audio_queues = NULL;
 
 	kfree(dev->_audiofilename);