Fix the most obvious compile warnings

src/modules/navigator/navigator_main.cpp

@@ -106,16 +106,16 @@ Navigator::Navigator() :
 	_onboard_mission_sub(-1),
 	_offboard_mission_sub(-1),
 	_pos_sp_triplet_pub(-1),
-	_vstatus({}),
-	_control_mode({}),
-	_global_pos({}),
-	_home_pos({}),
-	_mission_item({}),
-	_nav_caps({}),
-	_pos_sp_triplet({}),
+	_vstatus{},
+	_control_mode{},
+	_global_pos{},
+	_home_pos{},
+	_mission_item{},
+	_nav_caps{},
+	_pos_sp_triplet{},
 	_mission_item_valid(false),
 	_loop_perf(perf_alloc(PC_ELAPSED, "navigator")),
-	_geofence({}),
+	_geofence{},
 	_geofence_violation_warning_sent(false),
 	_fence_valid(false),
 	_inside_fence(true),