KVM: s390: Add new SIGP order to kernel counters

The new SIGP order Store Additional Status at Address is totally
handled by user space, but we should still record the occurrence
of this order in the kernel code.

Signed-off-by: Eric Farman <farman@linux.vnet.ibm.com>
Reviewed-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>