5042 stop using deprecated atomic functions

*** 91,101 ****
          hrtime_t *addr = &it->it_hrtime;
          hrtime_t old = *addr, new = gethrtime();
  
          do {
                  old = *addr;
!         } while (cas64((uint64_t *)addr, old, new) != old);
  
          timer_fire(it);
  }
  
  static int
--- 91,101 ----
          hrtime_t *addr = &it->it_hrtime;
          hrtime_t old = *addr, new = gethrtime();
  
          do {
                  old = *addr;
!         } while (atomic_cas_64((uint64_t *)addr, old, new) != old);
  
          timer_fire(it);
  }
  
  static int
*** 233,246 ****
          hrtime_t diff, now = gethrtime();
          hrtime_t *addr = &it->it_hrtime;
          hrtime_t last;
  
          /*
!          * We're using cas64() here only to assure that we slurp the entire
!          * timestamp atomically.
           */
!         last = cas64((uint64_t *)addr, 0, 0);
  
          *when = it->it_itime;
  
          if (!timerspecisset(&when->it_value))
                  return (0);
--- 233,246 ----
          hrtime_t diff, now = gethrtime();
          hrtime_t *addr = &it->it_hrtime;
          hrtime_t last;
  
          /*
!          * We're using atomic_cas_64() here only to assure that we slurp the
!          * entire timestamp atomically.
           */
!         last = atomic_cas_64((uint64_t *)addr, 0, 0);
  
          *when = it->it_itime;
  
          if (!timerspecisset(&when->it_value))
                  return (0);