s390/qdio: remove checks for ccw device internal state

Prior to starting IO qdio checks for the internal state of the ccw
device. These checks happen without locking, so consistency between
state evaluation and starting of the IO is not guaranteed.

Since the internal state is checked during ccw_device_start it is
safe to get rid of these additional checks.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>