Merge branch '6400-server-enabled' into 'develop'

Fix undefined variable firewall_server_enabled and xmpp_server_enabled, #6400

See merge request ispconfig/ispconfig3!1653

Author: Till Brehm

install/update.php

@@ -369,7 +369,7 @@
 unset($current_svc_config);
 
 //** Write new decisions into DB
-$sql = "UPDATE ?? SET mail_server = '{$conf['services']['mail']}', web_server = '{$conf['services']['web']}', dns_server = '{$conf['services']['dns']}', file_server = '{$conf['services']['file']}', db_server = '{$conf['services']['db']}', vserver_server = '{$conf['services']['vserver']}', proxy_server = '{$conf['services']['proxy']}', firewall_server = '$firewall_server_enabled', xmpp_server = '$xmpp_server_enabled' WHERE server_id = ?";
+$sql = "UPDATE ?? SET mail_server = '{$conf['services']['mail']}', web_server = '{$conf['services']['web']}', dns_server = '{$conf['services']['dns']}', file_server = '{$conf['services']['file']}', db_server = '{$conf['services']['db']}', vserver_server = '{$conf['services']['vserver']}', proxy_server = '{$conf['services']['proxy']}', firewall_server = '{$conf['services']['firewall']}', xmpp_server = '{$conf['services']['xmpp']}' WHERE server_id = ?";
 $inst->db->query($sql, $conf['mysql']['database'].'.server', $conf['server_id']);
 if($conf['mysql']['master_slave_setup'] == 'y') {
 	$inst->dbmaster->query($sql, $conf['mysql']['master_database'].'.server', $conf['server_id']);