Visualization of TriangleMeshModel

### Checklist

- [X] I have searched for [similar issues](https://github.com/isl-org/Open3D/issues).
- [X] For Python issues, I have tested with the [latest development wheel](http://www.open3d.org/docs/latest/getting_started.html#development-version-pip).
- [X] I have checked the [release documentation](http://www.open3d.org/docs/release/) and the [latest documentation](http://www.open3d.org/docs/latest/) (for `master` branch).

### My Question

Hello,
I have been trying to visualize 3D models in Open3D-Python by using the following code:

`import open3d as o3d`
`model = o3d.io.read_triangle_model("nk1.glb")
o3d.visualization.draw_geometries([model])
`

The problem is that:-
`o3d.visualization.draw_geometries([model])` works for **Triangle mesh**, but not for **TriangleMeshModel**. It returns the error: 

> draw_geometries(): incompatible function arguments. Invoked with: