ekf: add range finder kinematic consistency check

At each new valid range measurement, the time derivative of the distance
to the ground is computed and compared with the estimated velocity.
The average of a normalized innovation squared statistic check is used
to detect a bias in the derivative of distance measurement,
indicating that the distance measurements are kinematically inconsistent
with the filter.

src/modules/ekf2/EKF/estimator_interface.h

@@ -63,6 +63,7 @@
 #include "common.h"
 #include "RingBuffer.h"
 #include "imu_down_sampler.hpp"
+#include "range_finder_consistency_check.hpp"
 #include "sensor_range_finder.hpp"
 #include "utils.hpp"
 
@@ -297,6 +298,8 @@ protected:
 	extVisionSample _ev_sample_delayed_prev{};
 	dragSample _drag_down_sampled{};	// down sampled drag specific force data (filter prediction rate -> observation rate)
 
+	RangeFinderConsistencyCheck _rng_consistency_check;
+
 	float _air_density{CONSTANTS_AIR_DENSITY_SEA_LEVEL_15C};		// air density (kg/m**3)
 
 	// Sensor limitations