[Optim in backward] register_hook=False API (#95096)
Use this API to avoid registering hooks for applications that do their
own custom logic. This eliminates the need for DDP to have to de-register these
hooks.
Differential Revision: [D43383794](https://our.internmc.facebook.com/intern/diff/D43383794/)
**NOTE FOR REVIEWERS**: This PR has internal Meta-specific changes or comments, please review them on [Phabricator](https://our.internmc.facebook.com/intern/diff/D43383794/)!
Pull Request resolved: https://github.com/pytorch/pytorch/pull/95096
Approved by: https://github.com/zhaojuanmao
