Apply selective build on RNN operators (#44132)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/44132
Pull Request resolved: https://github.com/pytorch/pytorch/pull/43985
Added
```
def(detail::SelectiveStr<true>, ...)
impl(detail::SelectiveStr<true>, ...)
```
in torch/library, which can also be used for other templated selective registration.
Size saves for this diff:
fbios-pika: 78 KB
igios: 87 KB
Test Plan: Imported from OSS
Reviewed By: ljk53, smessmer
Differential Revision: D23459774
Pulled By: iseeyuan
fbshipit-source-id: 86d34cfe8e3f852602f203db06f23fa99af2c018
