Preserve user specified attributes and methods (#38830)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/38830
This patch enables to preserve user specified attributes or non forward
methods. The API:
_freeze_module(Module, ["a", "version"])
Test Plan: Imported from OSS
Differential Revision: D21957316
Pulled By: bzinodev
fbshipit-source-id: 5c9146ae679791070a9de868c45785725b48a9e6
