vmm/virtualbox: No longer save machine settings in detach_ide_disk()
vmm/virtualbox: No longer save machine settings in detach_ide_disk()

- Move responsibility for saving machine settings from detach_ide_disk()
to unregister_machine()

- Only save settings once in unregister_machine()

cmusatyalab/openisr,cmusatyalab/openisr,cmusatyalab/openisr,cmusatyalab/openisr,cmusatyalab/openisr