pytorch

8a1a93a9 - port Bazel //tools/autograd to shared build structure

port Bazel //tools/autograd to shared build structure Pull Request resolved: https://github.com/pytorch/pytorch/pull/74749 Differential Revision: [D35145072](https://our.internmc.facebook.com/intern/diff/D35145072/) **NOTE FOR REVIEWERS**: This PR has internal Facebook specific changes or comments, please review them on [Phabricator](https://our.internmc.facebook.com/intern/diff/D35145072/)! Approved by: https://github.com/albanD