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

*** 258,270 ****
             it is available) for managing the service.
  
  
         general/single_instance
  
!            If single_instance is set to true, svc.startd only allows one
!            instance of this service to transition to online or degraded at any
!            time.
  
  
  
         Additionally, svc.startd managed services can define the optional
         properties listed below in the startd property group.
--- 258,272 ----
             it is available) for managing the service.
  
  
         general/single_instance
  
!            This was originally supposed to ensure that only one service
!            instance could be in online or degraded state at once; however, it
!            was never implemented, and is often incorrectly specified in multi-
!            instance manifests. As such, it should be considered obsolete and
!            not specified in new manifests.
  
  
  
         Additionally, svc.startd managed services can define the optional
         properties listed below in the startd property group.
*** 435,440 ****
         scf_value_is_type(3SCF), contract(4), init.d(4), process(4),
         inittab(4), attributes(5), smf(5), smf_method(5)
  
  
  
!                                 March 18, 2011                  SVC.STARTD(1M)
--- 437,442 ----
         scf_value_is_type(3SCF), contract(4), init.d(4), process(4),
         inittab(4), attributes(5), smf(5), smf_method(5)
  
  
  
!                                December 11, 2019                SVC.STARTD(1M)