AP_AHRS: removed get_roll_rate_earth() and get_pitch_rate_earth()

these are not used any more

libraries/AP_AHRS/AP_AHRS.cpp

@@ -100,19 +100,6 @@ const AP_Param::GroupInfo AP_AHRS::var_info[] PROGMEM = {
     AP_GROUPEND
 };
 
-// get pitch rate in earth frame, in radians/s
-float AP_AHRS::get_pitch_rate_earth(void) const
-{
-	Vector3f omega = get_gyro();
-	return cosf(roll) * omega.y - sinf(roll) * omega.z;
-}
-
-// get roll rate in earth frame, in radians/s
-float AP_AHRS::get_roll_rate_earth(void) const {
-	Vector3f omega = get_gyro();
-	return omega.x + tanf(pitch)*(omega.y*sinf(roll) + omega.z*cosf(roll));
-}
-
 // return airspeed estimate if available
 bool AP_AHRS::airspeed_estimate(float *airspeed_ret)
 {

libraries/AP_AHRS/AP_AHRS.h

@@ -97,10 +97,6 @@ public:
     int32_t pitch_sensor;
     int32_t yaw_sensor;
 
-    // roll and pitch rates in earth frame, in radians/s
-    float get_pitch_rate_earth(void) const;
-    float get_roll_rate_earth(void) const;
-
     // return a smoothed and corrected gyro vector
     virtual const Vector3f get_gyro(void) const = 0;