mac80211: flush queues before deauth/disassoc

On deauth/disassoc we tear down all BA sessions. These
DELBA packets are sent on the appropriate TID, while
deauth/disassoc is always sent on VO. This sometimes
ends with the DELBA being sent after the deauth was
already sent.

Fix it by flushing all the pending frames before
sending deauth/disassoc.
Signed-off-by: Eliad Peller <eliad@wizery.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

net/mac80211/mlme.c

@@ -1364,6 +1364,10 @@ static void ieee80211_set_disassoc(struct ieee80211_sub_if_data *sdata,
 	}
 	mutex_unlock(&local->sta_mtx);
 
+	/* flush out any pending frame (e.g. DELBA) before deauth/disassoc */
+	if (tx)
+		drv_flush(local, false);
+
 	/* deauthenticate/disassociate now */
 	if (tx || frame_buf)
 		ieee80211_send_deauth_disassoc(sdata, bssid, stype, reason,