webui: remove default stream socket context options

Do not enforce a specific bindto (ipv4/ipv6) by stream context options.

See:

https://www.php.net/manual/en/context.socket.php
https://www.php.net/manual/de/function.stream-context-create.php

Fixes #579: Unable to connect to the director from webui via ipv6

webui/vendor/Bareos/library/Bareos/BSock/BareosBSock.php

@@ -5,7 +5,7 @@
  * bareos-webui - Bareos Web-Frontend
  *
  * @link      https://github.com/bareos/bareos for the canonical source repository
- * @copyright Copyright (c) 2014-2019 Bareos GmbH & Co. KG
+ * @copyright Copyright (c) 2014-2021 Bareos GmbH & Co. KG
  * @license   GNU Affero General Public License (http://www.gnu.org/licenses/)
  *
  * This program is free software: you can redistribute it and/or modify
@@ -467,13 +467,10 @@ private function connect()
       $port = $this->config['port'];
       $remote = "tcp://" . $this->config['host'] . ":" . $port;
 
-      // set default stream context options
-      $opts = array(
-         'socket' => array(
-            'bindto' => '0:0',
-         ),
-      );
+      // set stream context options
+      $opts = array();
 
+      // create stream context
       $context = stream_context_create($opts);
 
       try {