Implement module.to_empty() (#56610)
Summary:
Fixes https://github.com/pytorch/pytorch/issues/54600
Pull Request resolved: https://github.com/pytorch/pytorch/pull/56610
Reviewed By: malfet
Differential Revision: D27921653
Pulled By: jbschlosser
fbshipit-source-id: 10734b3eaa5b84bb4ba6eeba1043cfc8bb570a17
