px4_work_queue: command line status output and shutdown empty queues

* adds a work_queue systemcmd that will bring a tree view of all active work queues and work items
 * WorkQueues now track attached WorkItems and will shutdown when the last WorkItem is detached

src/drivers/distance_sensor/leddar_one/leddar_one.cpp

@@ -174,7 +174,7 @@ private:
 
 LeddarOne::LeddarOne(const char *device_path, const char *serial_port, uint8_t device_orientation):
 	CDev(device_path),
-	ScheduledWorkItem(px4::wq_configurations::hp_default),
+	ScheduledWorkItem(MODULE_NAME, px4::wq_configurations::hp_default),
 	_px4_rangefinder(0 /* device id not yet used */, ORB_PRIO_DEFAULT, device_orientation)
 {
 	_serial_port = strdup(serial_port);