zd1211rw: fix ack_pending in filter_ack causing tx-packet ordering problem on monitor

For reasons not very clear yet to me, filter_ack leaves matching tx-packet
pending with 'ack_pending'. This causes tx-packet to be passed back to upper
layer after next packet has been transfered and tx-packets might end up
coming come out of monitor interface in wrong order vs. rx.

Because of this when enable AP-mode, hostapd monitor interface would get
packets in wrong order causing problems in WPA association.

So don't use mac->ack_pending when in AP-mode.
Signed-off-by: Jussi Kivilinna <jussi.kivilinna@mbnet.fi>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/zd1211rw/zd_mac.c

@@ -799,6 +799,13 @@ static int filter_ack(struct ieee80211_hw *hw, struct ieee80211_hdr *rx_hdr,
 
 		mac->ack_pending = 1;
 		mac->ack_signal = stats->signal;
+
+		/* Prevent pending tx-packet on AP-mode */
+		if (mac->type == NL80211_IFTYPE_AP) {
+			skb = __skb_dequeue(q);
+			zd_mac_tx_status(hw, skb, mac->ack_signal, NULL);
+			mac->ack_pending = 0;
+		}
 	}
 
 	spin_unlock_irqrestore(&q->lock, flags);