Cleanup unused args in max_unpooling3d (#39664)
Summary:
Reported by dlibenzi (thanks!) that these arguments are not used in the implementation.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/39664
Differential Revision: D21934989
Pulled By: ailzhang
fbshipit-source-id: 35e79ce7f49626c8ad79362f972e442c06022dcc
