navigator: correctly use all navigator modes

src/modules/navigator/navigator.h

@@ -65,9 +65,8 @@
 
 /**
  * Number of navigation modes that need on_active/on_inactive calls
- * Currently: mission, loiter, and rtl
  */
-#define NAVIGATOR_MODE_ARRAY_SIZE 4
+#define NAVIGATOR_MODE_ARRAY_SIZE 6
 
 class Navigator : public control::SuperBlock
 {

src/modules/navigator/navigator_main.cpp

@@ -141,6 +141,8 @@ Navigator::Navigator() :
 	_navigation_mode_array[1] = &_loiter;
 	_navigation_mode_array[2] = &_rtl;
 	_navigation_mode_array[3] = &_offboard;
+	_navigation_mode_array[4] = &_dataLinkLoss;
+	_navigation_mode_array[5] = &_engineFailure;
 
 	updateParams();
 }