AP_InertialSensor: remove unused rotation member

Author: peterbarker

libraries/AP_InertialSensor/AP_InertialSensor_L3G4200D.h

@@ -50,7 +50,5 @@ class AP_InertialSensor_L3G4200D : public AP_InertialSensor_Backend
     // Low Pass filters for gyro and accel 
     LowPassFilter2pVector3f _accel_filter;
     LowPassFilter2pVector3f _gyro_filter;
-
-    enum Rotation _rotation; 
 };
-#endif // __AP_INERTIAL_SENSOR_L3G4200D2_H__
+#endif // __AP_INERTIAL_SENSOR_L3G4200D2_H__