ath10k: switch to ieee80211_tx_dequeue_ni

Since ath10k_mac_tx_push_txq() can be called from process context, we
must explicitly disable softirqs before the call into mac80211.

By calling ieee80211_tx_dequeue_ni() instead of ieee80211_tx_dequeue()
we make sure softirqs are always disabled even in the case when
ath10k_mac_tx_push_txq() is called from process context.

Calling ieee80211_tx_dequeue_ni() with softirq's already disabled
(e.g., from softirq context) should be safe as the local_bh_disable()
and local_bh_enable() functions (called from ieee80211_tx_dequeue_ni)
are fully reentrant.
Signed-off-by: Erik Stromdahl <erik.stromdahl@gmail.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

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

@@ -4065,7 +4065,7 @@ int ath10k_mac_tx_push_txq(struct ieee80211_hw *hw,
 	if (ret)
 		return ret;
 
-	skb = ieee80211_tx_dequeue(hw, txq);
+	skb = ieee80211_tx_dequeue_ni(hw, txq);
 	if (!skb) {
 		spin_lock_bh(&ar->htt.tx_lock);
 		ath10k_htt_tx_dec_pending(htt);