12071 clarify implementation of single_instance in SMF services
Reviewed by: Robert Mustacchi <rm@fingolfin.org>

*** 1,10 ****
--- 1,11 ----
  <?xml version="1.0"?>
  <!DOCTYPE service_bundle SYSTEM "/usr/share/lib/xml/dtd/service_bundle.dtd.1">
  <!--
   Copyright (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved.
   Copyright 2016 Hans Rosenfeld <rosenfeld@grumpf.hope-2000.org>
+  Copyright 2019 Joyent, Inc.
  
   CDDL HEADER START
  
   The contents of this file are subject to the terms of the
   Common Development and Distribution License (the "License").
*** 100,110 ****
                          </prop_pattern>
                          <prop_pattern name='single_instance' type='boolean'
                              required='false'>
                                  <description>
                                          <loctext xml:lang='C'>
! Only one instance of this service may be run.  This property is currently unenforced, but will be at some point in the future.
                                          </loctext>
                                  </description>
                                  <cardinality min='1' max='1'/>
                          </prop_pattern>
                  </pg_pattern>
--- 101,111 ----
                          </prop_pattern>
                          <prop_pattern name='single_instance' type='boolean'
                              required='false'>
                                  <description>
                                          <loctext xml:lang='C'>
! Only one instance of this service may be run.  This behavior is unimplemented, and obsolete.
                                          </loctext>
                                  </description>
                                  <cardinality min='1' max='1'/>
                          </prop_pattern>
                  </pg_pattern>