(legacy) missed a dependency in load_balancer_pool.php

src/www/load_balancer_pool.php

@@ -32,7 +32,7 @@ require_once("filter.inc");
 require_once("load_balancer_maintable.inc");
 require_once("services.inc");
 require_once("vslb.inc");
-
+require_once("interfaces.inc");
 
 if (!is_array($config['load_balancer']['lbpool'])) {
 	$config['load_balancer']['lbpool'] = array();