rx_aar: unreference dialog in case of aar update (kamailio#3104)

- release the dialog reference even for aar updates as the dialog was
  already referenced when issuing the aar request

Co-authored-by: Atanas Bakalov <atanas@wgtwo.com>
(cherry picked from commit ab8cb43)

src/modules/ims_qos/rx_aar.c

@@ -177,6 +177,8 @@ void async_aar_callback(int is_timeout, void *param, AAAMessage *aaa, long elaps
             STR_SHM_DUP(*passed_rx_session_id, aaa->sessionId->data, "cb_passed_rx_session_id");
             LM_DBG("passed rx session id [%.*s]", passed_rx_session_id->len, passed_rx_session_id->s);
             dlgb.register_dlgcb_nodlg( data->dlg, DLGCB_TERMINATED | DLGCB_DESTROY | DLGCB_EXPIRED | DLGCB_RESPONSE_WITHIN | DLGCB_CONFIRMED | DLGCB_FAILED, callback_dialog, (void*) (passed_rx_session_id), free_dialog_data);
+        } else {
+            unref_dlg(data->dlg, 1);
         }
         result = CSCF_RETURN_TRUE;
     } else {