mwl8k: Call ieee80211_stop_tx_ba_cb_irqsafe for already deleted BA stream

When stack calls ampdu_action with action = IEEE80211_AMPDU_TX_STOP
for a stream that has already been removed from the driver, call
ieee80211_tx_ba_stop_irqsafe to clear the stream in the stack.
Signed-off-by: Yogesh Ashok Powar <yogeshp@marvell.com>
Signed-off-by: Nishant Sarmukadam <nishants@marvell.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/mwl8k.c

@@ -5044,14 +5044,14 @@ mwl8k_ampdu_action(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
 		ieee80211_start_tx_ba_cb_irqsafe(vif, addr, tid);
 		break;
 	case IEEE80211_AMPDU_TX_STOP:
-		if (stream == NULL)
-			break;
-		if (stream->state == AMPDU_STREAM_ACTIVE) {
-			spin_unlock(&priv->stream_lock);
-			mwl8k_destroy_ba(hw, stream);
-			spin_lock(&priv->stream_lock);
+		if (stream) {
+			if (stream->state == AMPDU_STREAM_ACTIVE) {
+				spin_unlock(&priv->stream_lock);
+				mwl8k_destroy_ba(hw, stream);
+				spin_lock(&priv->stream_lock);
+			}
+			mwl8k_remove_stream(hw, stream);
 		}
-		mwl8k_remove_stream(hw, stream);
 		ieee80211_stop_tx_ba_cb_irqsafe(vif, addr, tid);
 		break;
 	case IEEE80211_AMPDU_TX_OPERATIONAL: