Preserve module names in recursive script (#24505)
Summary:
Turns
```
ScriptModule(
(conv): ScriptModule()
(lin): ScriptModule()
(sub): ScriptModule()
)
```
into
```
ScriptModule(
original=MyModule
(conv): ScriptModule(original=Conv2d)
(lin): ScriptModule(original=Linear)
(sub): ScriptModule(original=Submodule)
)
```
](https://our.intern.facebook.com/intern/diff/16862032/)
Pull Request resolved: https://github.com/pytorch/pytorch/pull/24505
Pulled By: driazati
Differential Revision: D16862032
fbshipit-source-id: 76dc4e5252bbf746f5cc26450b577dab10477732
