AP_NavEKF3: use filtered gyro in INS position correction

this reduces the impact of IMU noise on the output velocity from the
EKF

libraries/AP_NavEKF3/AP_NavEKF3_core.cpp

@@ -863,7 +863,7 @@ void NavEKF3_core::calcOutputStates()
     if (!accelPosOffset.is_zero()) {
         // calculate the average angular rate across the last IMU update
         // note delAngDT is prevented from being zero in readIMUData()
-        Vector3F angRate = imuDataNew.delAng * (1.0f/imuDataNew.delAngDT);
+        Vector3F angRate = dal.ins().get_gyro(gyro_index_active).toftype();
 
         // Calculate the velocity of the body frame origin relative to the IMU in body frame
         // and rotate into earth frame. Note % operator has been overloaded to perform a cross product