This prepares for moving the halted field to CPUState.
Most call sites can already supply S390CPU, for some env becomes unused.
Signed-off-by: Andreas Färber <afaerber@suse.de>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Alexander Graf <agraf@suse.de>