XXXX introduce drv_sectohz

*** 1089,1099 ****
          if (sv_mod_status == SV_PREVENT_UNLOAD) {
                  if ((sv_ndevices != 0) || (sv_tset != NULL)) {
                          rc = EBUSY;
                  } else {
                          sv_mod_status = SV_ALLOW_UNLOAD;
!                         delay(SV_WAIT_UNLOAD * drv_usectohz(1000000));
                  }
          }
  
          mutex_exit(&sv_mutex);
          return (rc);
--- 1089,1099 ----
          if (sv_mod_status == SV_PREVENT_UNLOAD) {
                  if ((sv_ndevices != 0) || (sv_tset != NULL)) {
                          rc = EBUSY;
                  } else {
                          sv_mod_status = SV_ALLOW_UNLOAD;
!                         delay(drv_sectohz(SV_WAIT_UNLOAD));
                  }
          }
  
          mutex_exit(&sv_mutex);
          return (rc);