net: wireless: rt2x00: Staticize rt2x00queue_pause_queue_nocheck()

rt2x00queue_pause_queue_nocheck()is used only in this file.
Fix the following sparse warning:

drivers/net/wireless/rt2x00/rt2x00queue.c:939:6: warning: symbol 'rt2x00queue_pause_queue_nocheck' was not declared. Should it be
static?
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Acked-by: Gertjan van Wingerde <gwingerde@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/rt2x00/rt2x00queue.c

@@ -936,7 +936,7 @@ void rt2x00queue_index_inc(struct queue_entry *entry, enum queue_index index)
 	spin_unlock_irqrestore(&queue->index_lock, irqflags);
 }
 
-void rt2x00queue_pause_queue_nocheck(struct data_queue *queue)
+static void rt2x00queue_pause_queue_nocheck(struct data_queue *queue)
 {
 	switch (queue->qid) {
 	case QID_AC_VO: