More t()

Update more t() calls

mod/maintenance.php

@@ -1,10 +1,13 @@
 <?php
-
+/**
+ * @file mod/maintenance.php
+ */
 use Friendica\App;
 use Friendica\Core\Config;
+use Friendica\Core\L10n;
 
-function maintenance_content(App $a) {
-
+function maintenance_content(App $a)
+{
 	$reason = Config::get('system', 'maintenance_reason');
 
 	if (substr(normalise_link($reason), 0, 7) == 'http://') {
@@ -18,7 +21,7 @@ function maintenance_content(App $a) {
 	header('Retry-After: 600');
 
 	return replace_macros(get_markup_template('maintenance.tpl'), [
-		'$sysdown' => t('System down for maintenance'),
+		'$sysdown' => L10n::t('System down for maintenance'),
 		'$reason' => $reason
 	]);
 }