ath9k: use ieee80211_free_txskb

Using ieee80211_free_txskb for tx frames is required, since mac80211 clones
skbs for which socket tx status is requested.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Cc: stable@vger.kernel.org
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/ath/ath9k/beacon.c b/drivers/net/wireless/ath/ath9k/beacon.c
index 76f07d8..1b48414 100644
--- a/drivers/net/wireless/ath/ath9k/beacon.c
+++ b/drivers/net/wireless/ath/ath9k/beacon.c
@@ -120,7 +120,7 @@
 
 	if (ath_tx_start(hw, skb, &txctl) != 0) {
 		ath_dbg(common, XMIT, "CABQ TX failed\n");
-		dev_kfree_skb_any(skb);
+		ieee80211_free_txskb(hw, skb);
 	}
 }