precland: add a method to check if precland is activated

src/modules/navigator/precland.cpp

@@ -101,6 +101,8 @@ PrecLand::on_activation()
 	_last_slewrate_time = 0;
 
 	switch_to_state_start();
+
+	_is_activated = true;
 }
 
 void
@@ -158,6 +160,12 @@ PrecLand::on_active()
 
 }
 
+void
+PrecLand::on_inactivation()
+{
+	_is_activated = false;
+}
+
 void
 PrecLand::updateParams()
 {

src/modules/navigator/precland.h

@@ -72,11 +72,14 @@ public:
 
 	void on_activation() override;
 	void on_active() override;
+	void on_inactivation() override;
 
 	void set_mode(PrecLandMode mode) { _mode = mode; };
 
 	PrecLandMode get_mode() { return _mode; };
 
+	bool is_activated() { return _is_activated; };
+
 private:
 
 	void updateParams() override;
@@ -125,6 +128,8 @@ private:
 
 	PrecLandMode _mode{PrecLandMode::Opportunistic};
 
+	bool _is_activated {false}; /**< indicates if precland is activated */
+
 	DEFINE_PARAMETERS(
 		(ParamFloat<px4::params::PLD_BTOUT>) _param_pld_btout,
 		(ParamFloat<px4::params::PLD_HACC_RAD>) _param_pld_hacc_rad,