Added room in land_detector code for free-fall detection

src/modules/land_detector/FixedwingLandDetector.h

@@ -49,6 +49,9 @@
 #include <uORB/topics/airspeed.h>
 #include <systemlib/param/param.h>
 
+namespace landdetection
+{
+
 class FixedwingLandDetector : public LandDetector
 {
 public:
@@ -58,7 +61,7 @@ protected:
 	/**
 	* @brief  blocking loop, should be run in a separate thread or task. Runs at 50Hz
 	**/
-	bool update() override;
+	LandDetectionResult update() override;
 
 	/**
 	* @brief Initializes the land detection algorithm
@@ -70,6 +73,16 @@ protected:
 	**/
 	void updateSubscriptions();
 
+	/**
+	* @brief get UAV landed state
+	**/
+	bool get_landed_state();
+
+	/**
+	* @brief returns true if UAV is in free-fall state
+	**/
+	bool get_freefall_state();
+
 private:
 	/**
 	* @brief download and update local parameter cache
@@ -109,4 +122,6 @@ private:
 	uint64_t _landDetectTrigger;
 };
 
+}
+
 #endif //__FIXED_WING_LAND_DETECTOR_H__