AP_Motors: fixed example build

libraries/AP_Motors/examples/AP_Motors_test/AP_Motors_test.pde

@@ -17,6 +17,20 @@
 #include <AP_Motors.h>
 #include <AP_Curve.h>
 #include <AP_Notify.h>
+#include <AP_GPS.h>
+#include <DataFlash.h>
+#include <AP_InertialSensor.h>
+#include <AP_ADC.h>
+#include <GCS_MAVLink.h>
+#include <AP_Baro.h>
+#include <Filter.h>
+#include <AP_AHRS.h>
+#include <AP_Compass.h>
+#include <AP_Declination.h>
+#include <AP_Airspeed.h>
+#include <AP_Vehicle.h>
+#include <AP_ADC_AnalogSource.h>
+#include <AP_Mission.h>
 
 const AP_HAL::HAL& hal = AP_HAL_BOARD_DRIVER;