smf: switch to a tri-state for process-security properties true=on,false=off,nil=default

*** 594,604 ****
   * nvlist_t
   */
  int _scf_notify_get_params(scf_propertygroup_t *, nvlist_t *);
  
  #if !defined(NATIVE_BUILD)
! int scf_default_secflags(scf_handle_t *, psecflags_t *);
  #endif
  
  #define SCF_NOTIFY_PARAMS_SOURCE_NAME   ((const char *)"preference_source")
  
  #ifdef  __cplusplus
--- 594,604 ----
   * nvlist_t
   */
  int _scf_notify_get_params(scf_propertygroup_t *, nvlist_t *);
  
  #if !defined(NATIVE_BUILD)
! int scf_default_secflags(scf_handle_t *, scf_secflags_t *);
  #endif
  
  #define SCF_NOTIFY_PARAMS_SOURCE_NAME   ((const char *)"preference_source")
  
  #ifdef  __cplusplus