mac80211: Decrease number of explicit ->tx_queue references.

Accomplish this by using local variables.
Signed-off-by: David S. Miller <davem@davemloft.net>

net/mac80211/main.c

@@ -570,6 +570,7 @@ static int ieee80211_stop(struct net_device *dev)
 int ieee80211_start_tx_ba_session(struct ieee80211_hw *hw, u8 *ra, u16 tid)
 {
 	struct ieee80211_local *local = hw_to_local(hw);
+	struct netdev_queue *txq;
 	struct sta_info *sta;
 	struct ieee80211_sub_if_data *sdata;
 	u16 start_seq_num = 0;
@@ -636,7 +637,8 @@ int ieee80211_start_tx_ba_session(struct ieee80211_hw *hw, u8 *ra, u16 tid)
 
 	/* ensure that TX flow won't interrupt us
 	 * until the end of the call to requeue function */
-	spin_lock_bh(&local->mdev->tx_queue.lock);
+	txq = &local->mdev->tx_queue;
+	spin_lock_bh(&txq->lock);
 
 	/* create a new queue for this aggregation */
 	ret = ieee80211_ht_agg_queue_add(local, sta, tid);
@@ -675,7 +677,7 @@ int ieee80211_start_tx_ba_session(struct ieee80211_hw *hw, u8 *ra, u16 tid)
 
 	/* Will put all the packets in the new SW queue */
 	ieee80211_requeue(local, ieee802_1d_to_ac[tid]);
-	spin_unlock_bh(&local->mdev->tx_queue.lock);
+	spin_unlock_bh(&txq->lock);
 	spin_unlock_bh(&sta->lock);
 
 	/* send an addBA request */
@@ -701,7 +703,7 @@ int ieee80211_start_tx_ba_session(struct ieee80211_hw *hw, u8 *ra, u16 tid)
 err_unlock_queue:
 	kfree(sta->ampdu_mlme.tid_tx[tid]);
 	sta->ampdu_mlme.tid_tx[tid] = NULL;
-	spin_unlock_bh(&local->mdev->tx_queue.lock);
+	spin_unlock_bh(&txq->lock);
 	ret = -EBUSY;
 err_unlock_sta:
 	spin_unlock_bh(&sta->lock);
@@ -826,6 +828,7 @@ EXPORT_SYMBOL(ieee80211_start_tx_ba_cb);
 void ieee80211_stop_tx_ba_cb(struct ieee80211_hw *hw, u8 *ra, u8 tid)
 {
 	struct ieee80211_local *local = hw_to_local(hw);
+	struct netdev_queue *txq;
 	struct sta_info *sta;
 	u8 *state;
 	int agg_queue;
@@ -875,10 +878,11 @@ void ieee80211_stop_tx_ba_cb(struct ieee80211_hw *hw, u8 *ra, u8 tid)
 
 	/* avoid ordering issues: we are the only one that can modify
 	 * the content of the qdiscs */
-	spin_lock_bh(&local->mdev->tx_queue.lock);
+	txq = &local->mdev->tx_queue;
+	spin_lock_bh(&txq->lock);
 	/* remove the queue for this aggregation */
 	ieee80211_ht_agg_queue_remove(local, sta, tid, 1);
-	spin_unlock_bh(&local->mdev->tx_queue.lock);
+	spin_unlock_bh(&txq->lock);
 
 	/* we just requeued the all the frames that were in the removed
 	 * queue, and since we might miss a softirq we do netif_schedule.