estimator_status delete unused nan_flags

msg/estimator_status.msg

@@ -6,7 +6,6 @@ float32[3] vibe			# IMU vibration metrics in the following array locations
 # 1 : Gyro high frequency vibe = filtered length of (delta_angle - prev_delta_angle)
 # 2 : Accel high frequency vibe = filtered length of (delta_velocity - prev_delta_velocity)
 
-uint8 nan_flags			# Bitmask to indicate NaN states
 uint8 health_flags		# Bitmask to indicate sensor health states (vel, pos, hgt)
 uint8 timeout_flags		# Bitmask to indicate timeout flags (vel, pos, hgt)
 float32[24] covariances	# Diagonal Elements of Covariance Matrix

src/modules/ekf2/ekf2_main.cpp

@@ -1428,7 +1428,6 @@ void Ekf2::run()
 			_ekf.get_ekf_soln_status(&status.solution_status_flags);
 			_ekf.get_imu_vibe_metrics(status.vibe);
 			status.time_slip = _last_time_slip_us / 1e6f;
-			status.nan_flags = 0.0f; // unused
 			status.health_flags = 0.0f; // unused
 			status.timeout_flags = 0.0f; // unused
 			status.pre_flt_fail = _preflt_fail;

src/modules/local_position_estimator/BlockLocalPositionEstimator.cpp

@@ -622,7 +622,6 @@ void BlockLocalPositionEstimator::publishEstimatorStatus()
 	}
 
 	_pub_est_status.get().n_states = n_x;
-	_pub_est_status.get().nan_flags = 0;
 	_pub_est_status.get().health_flags = _sensorFault;
 	_pub_est_status.get().timeout_flags = _sensorTimeout;
 	_pub_est_status.get().pos_horiz_accuracy = _pub_gpos.get().eph;

src/modules/mavlink/mavlink_messages.cpp

@@ -2203,7 +2203,6 @@ protected:
 				msg.covariance[i] = est.covariances[i];
 			}
 
-			msg.covariance[9] = est.nan_flags;
 			msg.covariance[10] = est.health_flags;
 			msg.covariance[11] = est.timeout_flags;