wifi: mac80211: fix AddBA response addressing

Since this frame is addressed from/to an MLD, it should be
built with the correct AP MLD address (in station mode) to
be encrypted properly.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

net/mac80211/agg-rx.c

@@ -242,7 +242,7 @@ static void ieee80211_send_addba_resp(struct sta_info *sta, u8 *da, u16 tid,
 	    sdata->vif.type == NL80211_IFTYPE_MESH_POINT)
 		memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
 	else if (sdata->vif.type == NL80211_IFTYPE_STATION)
-		memcpy(mgmt->bssid, sdata->deflink.u.mgd.bssid, ETH_ALEN);
+		memcpy(mgmt->bssid, sdata->vif.cfg.ap_addr, ETH_ALEN);
 	else if (sdata->vif.type == NL80211_IFTYPE_ADHOC)
 		memcpy(mgmt->bssid, sdata->u.ibss.bssid, ETH_ALEN);