osd: Make osd can dynamic set optracker via asok.

Signed-off-by: Jianpeng Ma <jianpeng.ma@intel.com>
(cherry picked from commit 4aaa123)

src/osd/OSD.cc

@@ -8616,6 +8616,7 @@ const char** OSD::get_tracked_conf_keys() const
     "osd_min_recovery_priority",
     "osd_op_complaint_time", "osd_op_log_threshold",
     "osd_op_history_size", "osd_op_history_duration",
+    "osd_enable_op_tracker",
     "osd_map_cache_size",
     "osd_map_max_advance",
     "osd_pg_epoch_persisted_max_stale",
@@ -8652,6 +8653,9 @@ void OSD::handle_conf_change(const struct md_config_t *conf,
     op_tracker.set_history_size_and_duration(cct->_conf->osd_op_history_size,
                                              cct->_conf->osd_op_history_duration);
   }
+  if (changed.count("osd_enable_op_tracker")) {
+      op_tracker.set_tracking(cct->_conf->osd_enable_op_tracker);
+  }
   if (changed.count("osd_disk_thread_ioprio_class") ||
       changed.count("osd_disk_thread_ioprio_priority")) {
     set_disk_tp_priority();