trim the $_GET['regcode']

Please add a trim to check_plain($_GET['regcode'])

If someone add a space like ?regcode=%20CODE regcode_load from that code will fail

  if (isset($_GET['regcode'])) {
        $form['regcode']['regcode_code']['#value']       = check_plain($_GET['regcode']);
        $form['regcode']['regcode_code']['#description'] = NULL;

New code with fix:

  if (isset($_GET['regcode'])) {
        $form['regcode']['regcode_code']['#value']       = trim(check_plain($_GET['regcode']));
        $form['regcode']['regcode_code']['#description'] = NULL;