ath9k: dynack: check da->enabled first in sampling routines

commit 9d3d65a9 upstream.

Check da->enabled flag first in ath_dynack_sample_tx_ts and
ath_dynack_sample_ack_ts routines in order to avoid useless
processing
Tested-by: Koen Vandeputte <koen.vandeputte@ncentric.com>
Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@redhat.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/net/wireless/ath/ath9k/dynack.c

@@ -184,7 +184,7 @@ void ath_dynack_sample_tx_ts(struct ath_hw *ah, struct sk_buff *skb,
 	struct ath_common *common = ath9k_hw_common(ah);
 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 
-	if ((info->flags & IEEE80211_TX_CTL_NO_ACK) || !da->enabled)
+	if (!da->enabled || (info->flags & IEEE80211_TX_CTL_NO_ACK))
 		return;
 
 	spin_lock_bh(&da->qlock);
@@ -266,7 +266,7 @@ void ath_dynack_sample_ack_ts(struct ath_hw *ah, struct sk_buff *skb,
 	struct ath_common *common = ath9k_hw_common(ah);
 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
 
-	if (!ath_dynack_bssidmask(ah, hdr->addr1) || !da->enabled)
+	if (!da->enabled || !ath_dynack_bssidmask(ah, hdr->addr1))
 		return;
 
 	spin_lock_bh(&da->qlock);