remove unneeded code

modules/monitoring/application/views/helpers/Perfdata.php

@@ -50,7 +50,7 @@ class Zend_View_Helper_Perfdata extends Zend_View_Helper_Abstract
         }
         // restore original column array sorting
         $headers = array();
-        foreach ($keys as $i => $column) {
+        foreach ($keys as $column) {
             if (isset($columns[$column])) {
                 $headers[$column] = $labels[$column];
             }