KVM: s390: trace correct values for set prefix and machine checks

When injecting SIGP set prefix or a machine check, we trace
the values in our per-vcpu local_int data structure instead
of the parameters passed to the function.

Fix this by changing the trace statement to use the correct values.

Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Jens Freimann <jfrei@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>