Irrlicht cleanup: cleanup various object to use RenderingEngine (#6088)

Irrlicht cleanup: cleanup various object to use RenderingEngine (#6088)

* Irrlicht cleanup: cleanup various object to use RenderingEngine

* CAO doesn't need scenemanager in addToScene
* Camera doesn't need VideoDriver pointer or SceneManager in constructor
* Hud doesn't need driver & scene manager in constructor
* Hud doesn't need scenemanager pointer
* Tile.h doesn't need IrrlichtDevice header (just SMaterial)
* WieldMeshSceneNode: only take scene, we always use scene root node as parent