fix problem with html select containing 0 as key

includes/sys_form.php

@@ -405,7 +405,7 @@ function html_select_key($dom_id, $name, $rows, $selected)
 {
     $html = '<select class="form-control" id="' . $dom_id . '" name="' . $name . '">';
     foreach ($rows as $key => $row) {
-        if (($key == $selected) || ($row == $selected)) {
+        if (($key == $selected) || ($row === $selected)) {
             $html .= '<option value="' . $key . '" selected="selected">' . $row . '</option>';
         } else {
             $html .= '<option value="' . $key . '">' . $row . '</option>';