s390x/kvm: avoid syscalls by syncing registers with kvm_run
We can avoid loads of syscalls when dropping to user space by storing the values
of more registers directly within kvm_run.
Support is added for:
- ARCH0: CPU timer, clock comparator, TOD programmable register,
guest breaking-event register, program parameter
- PFAULT: pfault parameters (token, select, compare)
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Jens Freimann <jfrei@linux.vnet.ibm.com> Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com> Acked-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>