s390/qdio: get rid of spin_lock_irqsave usage

All qdio functions that use spin_lock_irqsave are never used
from irq context. Thus it is safe to convert all of them to
use spin_lock_irq.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Reviewed-by: Ursula Braun <ubraun@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>