AP_Airspeed: show health status in examples

libraries/AP_Airspeed/examples/Airspeed/Airspeed.cpp

@@ -35,6 +35,8 @@ void setup()
     hal.console->println("ArduPilot Airspeed library test");
 
     AP_Param::set_object_value(&airspeed, airspeed.var_info, "_PIN", 65);
+    AP_Param::set_object_value(&airspeed, airspeed.var_info, "_ENABLE", 1);
+    AP_Param::set_object_value(&airspeed, airspeed.var_info, "_USE", 1);
 
     airspeed.init();
     airspeed.calibrate(false);
@@ -46,7 +48,7 @@ void loop(void)
     if((hal.scheduler->millis() - timer) > 100) {
         timer = hal.scheduler->millis();
         airspeed.read();
-        hal.console->printf("airspeed %.2f\n", airspeed.get_airspeed());
+        hal.console->printf("airspeed %.2f healthy=%u\n", airspeed.get_airspeed(), airspeed.healthy());
     }
     hal.scheduler->delay(1);
 }