connector: convert to single-threaded workqueue

From: Evgeniy Polyakov <johnpol@2ka.mipt.ru>

We don't need one cqueue thread for each CPU.  cqueue is used for
receiving userspace datagrams, which are very rare and thus will
happily live with a single queue.
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/connector/cn_queue.c

@@ -146,7 +146,7 @@ struct cn_queue_dev *cn_queue_alloc_dev(char *name, struct sock *nls)
 
 	dev->nls = nls;
 
-	dev->cn_queue = create_workqueue(dev->name);
+	dev->cn_queue = create_singlethread_workqueue(dev->name);
 	if (!dev->cn_queue) {
 		kfree(dev);
 		return NULL;