Add Go here circle visuals if in forward flight

Added circle visuals to the Go here map item to show the orbit pattern
that aircraft in forward flight will follow upon reaching the position.

This feature is already available in firmware that supports the
ORBIT_EXECUTION_STATUS MAVLink message, so this is only shown for
vehicles operating on firmware that lacks this support.

Author: rubenp02

src/FlightDisplay/FlyViewMap.qml

@@ -379,6 +379,44 @@ FlightMap {
         }
     }
 
+    // GoTo Location forward flight circle visuals
+    QGCMapCircleVisuals {
+        id:             fwdFlightGotoMapCircle
+        mapControl:     parent
+        mapCircle:      _fwdFlightGotoMapCircle
+        visible:        gotoLocationItem.visible && _activeVehicle &&
+                        _activeVehicle.inFwdFlight &&
+                        !_activeVehicle.orbitActive
+
+        Connections {
+            target: QGroundControl.multiVehicleManager
+            function onActiveVehicleChanged(activeVehicle) {
+                if (!activeVehicle) {
+                    visible = false
+                }
+            }
+        }
+
+        Binding {
+            target: _fwdFlightGotoMapCircle
+            property: "center"
+            value: gotoLocationItem.coordinate
+        }
+
+        QGCMapCircle {
+            id:                 _fwdFlightGotoMapCircle
+            interactive:        false
+            showRotation:       true
+            clockwiseRotation:  true
+
+            property real _defaultLoiterRadius: _flyViewSettings.forwardFlightGoToLocationLoiterRad.value
+
+            onCenterChanged: {
+                radius.rawValue = _defaultLoiterRadius
+            }
+        }
+    }
+
     // GoTo Location visuals
     MapQuickItem {
         id:             gotoLocationItem