Fix VLAN ID validation check to use the new VLAN ID

When checking the validity of VLAN ID based on RADIUS-based ACL or
accept_mac_file, the assigned vlan_id, not the old sta->vlan_id
(likely zero) needs to be used.

hostapd/ieee802_11.c

@@ -585,7 +585,7 @@ static void handle_auth(struct hostapd_data *hapd, struct ieee80211_mgmt *mgmt,
 
 	if (vlan_id > 0) {
 		if (hostapd_get_vlan_id_ifname(hapd->conf->vlan,
-					       sta->vlan_id) == NULL) {
+					       vlan_id) == NULL) {
 			hostapd_logger(hapd, sta->addr, HOSTAPD_MODULE_RADIUS,
 				       HOSTAPD_LEVEL_INFO, "Invalid VLAN ID "
 				       "%d received from RADIUS server",