KVM: s390: small fixes and enhancements

- selftest improvements
- yield improvements
- cleanups
KVM: s390: Do not yield when target is already running

If the target is already running we do not need to yield.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
1 file changed