Add boot_hrtime to global and zone kstats.

*** 21,30 ****
--- 21,31 ----
  /*
   * Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved.
   * Copyright 2013, Joyent, Inc. All rights reserved.
   * Copyright 2014 Nexenta Systems, Inc. All rights reserved.
   * Copyright 2014 Igor Kozhukhov <ikozhukhov@gmail.com>.
+  * Copyright 2016 Garrett D'Amore
   */
  
  #ifndef _SYS_ZONE_H
  #define _SYS_ZONE_H
  
*** 397,406 ****
--- 398,408 ----
          kstat_named_t   zm_fss_pri_avg;
          kstat_named_t   zm_ffcap;
          kstat_named_t   zm_ffnoproc;
          kstat_named_t   zm_ffnomem;
          kstat_named_t   zm_ffmisc;
+         kstat_named_t   zm_boot_hrtime;
  } zone_misc_kstat_t;
  
  typedef struct zone {
          /*
           * zone_name is never modified once set.
*** 514,523 ****
--- 516,526 ----
          hrtime_t        zone_pool_mod;  /* last pool bind modification time */
          /* zone_psetid is protected by cpu_lock */
          psetid_t        zone_psetid;    /* pset the zone is bound to */
  
          time_t          zone_boot_time; /* Similar to boot_time */
+         hrtime_t        zone_boot_hrtime; /* gethrtime() at zone boot */
  
          /*
           * The following two can be read without holding any locks.  They are
           * updated under cpu_lock.
           */