Set QGeoMapObjectPrivate::m_visible to true by default

Change-Id: I64ff6c1da227ff4da75944612badc646c5cba3c4
Reviewed-by: BogDan Vatra <bogdan@kdab.com>

src/location/declarativemaps/qgeomapobject_p_p.h

@@ -77,7 +77,7 @@ public:
     QGeoMapObject *q = nullptr;
     QPointer<QGeoMap> m_map;
     bool m_componentCompleted = false;
-    bool m_visible = false;
+    bool m_visible = true;
 
 protected:
     QGeoMapObjectPrivate(QGeoMapObject *q);