s390x: Fix vector stfle checks

134 is for bcd
135 is for the vector enhancements

Not the other way around...

Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Suggested-by: David Hildenbrand <david@redhat.com>