Port hardshrink to structured (#58663)
Summary: Pull Request resolved: https://github.com/pytorch/pytorch/pull/58663
Test Plan: Imported from OSS
Reviewed By: gchanan
Differential Revision: D28572531
Pulled By: ezyang
fbshipit-source-id: 3fc8c33445adeae1789774fb6d8099278b93f8f8
