[Listener] Fix Hello emission

The source interface is not forced to wifi_interface anymore.

infrastructure-centred/owlps-listener/owlps-listenerd.c

@@ -922,7 +922,7 @@ void autocalibrate_hello()
   send_sockfd =
     owlps_create_socket_to_aggregator(GET_AGGREGATION_IP(),
                                       GET_AUTOCALIBRATION_PORT(),
-                                      &serv, GET_WIFI_IFACE()) ;
+                                      &serv, NULL) ;
 
   memcpy(&message.ap_mac_addr_bytes, my_mac, 6) ;
   strncpy(message.ap_ip_addr, my_ip, 16) ;