grub_disk_dev_unregister (grub_disk_dev_t dev)
{
  grub_disk_dev_t *p, q;

  for (p = &grub_disk_dev_list, q = *p; q; p = &(q->next), q = q->next)
    if (q == dev)
      {
        *p = q->next;
	break;
      }
}
grub_disk_dev_unregister (grub_disk_dev_t dev)
{
  grub_disk_dev_t *p, q;

  for (p = &grub_disk_dev_list, q = *p; q; p = &(q->next), q = q->next)
    if (q == dev)
      {
        *p = q->next;
	break;
      }
}