Remove function variant of copy_ (#19622)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/19622
ghimport-source-id: 41eadd845e2cbd113735b8650dca39354e1c7f1d
Differential Revision: D15049274
Pulled By: li-roy
fbshipit-source-id: 4f7d7cb2c8339e5e7e35f95397fe6a3f4b7c74f3
