EKF: reduce scope of variable and remove redeclaration of member

EKF/EKFGSF_yaw.cpp

@@ -588,9 +588,8 @@ Matrix3f EKFGSF_yaw::ahrsPredictRotMat(const Matrix3f &R, const Vector3f &g)
 	ret(2,2) += R(2,0) * g(1) - R(2,1) * g(0);
 
 	// Renormalise rows
-	float rowLengthSq;
 	for (uint8_t r = 0; r < 3; r++) {
-		rowLengthSq = ret.row(r).norm_squared();
+		const float rowLengthSq = ret.row(r).norm_squared();
 		if (rowLengthSq > FLT_EPSILON) {
 			// Use linear approximation for inverse sqrt taking advantage of the row length being close to 1.0
 			const float rowLengthInv = 1.5f - 0.5f * rowLengthSq;

EKF/ekf.h

@@ -347,7 +347,6 @@ private:
 	uint64_t _time_last_of_fuse{0};		///< time the last fusion of optical flow measurements were performed (uSec)
 	uint64_t _time_last_arsp_fuse{0};	///< time the last fusion of airspeed measurements were performed (uSec)
 	uint64_t _time_last_beta_fuse{0};	///< time the last fusion of synthetic sideslip measurements were performed (uSec)
-	uint64_t _time_last_mag{0};		///< measurement time of last magnetomter sample (uSec)
 	uint64_t _time_last_fake_pos{0};	///< last time we faked position measurements to constrain tilt errors during operation without external aiding (uSec)
 
 	Vector2f _last_known_posNE;		///< last known local NE position vector (m)

EKF/estimator_interface.h

@@ -540,7 +540,7 @@ protected:
 	// timestamps of latest in buffer saved measurement in microseconds
 	uint64_t _time_last_imu{0};
 	uint64_t _time_last_gps{0};
-	uint64_t _time_last_mag{0};
+	uint64_t _time_last_mag{0}; ///< measurement time of last magnetomter sample (uSec)
 	uint64_t _time_last_baro{0};
 	uint64_t _time_last_range{0};
 	uint64_t _time_last_airspeed{0};