ath10k: make sure to not leak beacon dma mapping

If for some reason mac80211 wouldn't stop
beaconing gracefully and just removed interface of
a running AP/IBSS interface it was possible to
leak pending beacon DMA mapping. It's very
unlikely but better safe than sorry.
Signed-off-by: NMichal Kazior <michal.kazior@tieto.com>
Signed-off-by: NKalle Valo <kvalo@qca.qualcomm.com>

drivers/net/wireless/ath/ath10k/mac.c

@@ -2771,6 +2771,9 @@ static void ath10k_remove_interface(struct ieee80211_hw *hw,
 
 	spin_lock_bh(&ar->data_lock);
 	if (arvif->beacon) {
+		dma_unmap_single(arvif->ar->dev,
+				 ATH10K_SKB_CB(arvif->beacon)->paddr,
+				 arvif->beacon->len, DMA_TO_DEVICE);
 		dev_kfree_skb_any(arvif->beacon);
 		arvif->beacon = NULL;
 	}