[S390] cio: Use path verification to check for path state.

After I/O has been killed by the common I/O layer, trigger path
verification which will queue cio_device_nopath_notify itself if it
finds a device to be without paths.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>