ccw_device_clear — terminate I/O request processing
target ccw device
interruption parameter; value is only used if no I/O is outstanding, otherwise the intparm associated with the I/O request is returned
ccw_device_clear calls csch on cdev's subchannel.
0 on success, -ENODEV on device not operational, -EINVAL on invalid device state.
Interrupts disabled, ccw device lock held