allow pass ordered dict for nn sequential (#20796)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/20796
ghimport-source-id: 9f895a2a6ebc71984196b868dc3ea6a12286bc81
Differential Revision: D15505330
Pulled By: wanchaol
fbshipit-source-id: 2922c56606b477a34f4e6433fa790d5b2de9d77a
