[PATCH] s390: common i/o layer.

[PATCH] s390: common i/o layer.

 - Remove initialization of device.name.
 - Don't do put_device after failed get_device in get_ccwdev_by_busid.
 - Fix read_dev_chars and read_conf_data.
 - Call interrupt function of ccw device if path verification has been started.
 - Replace atomic_return_add by atomic_add_return in qdio.
 - Use wait_event instead of homegrown wait loop.
 - Fix reestablish queue problem.
 - Add ungroup attribute to ccw_group devices and add links from each
   ccw device of a group to the group device.
 - Use BUS_ID_SIZE instead of DEVICE_ID_SIZE.
 - Delay path verification if a basic sense is required.
 - Move qdio shutdown code from qdio_free to qdio_shutdown.