Remove old generating files from util (#1455)
Summary:
this is a non-ghstack copy of https://github.com/pytorch/benchmark/issues/1454
Pull Request resolved: https://github.com/pytorch/benchmark/pull/1455
Reviewed By: xuzhao9
Differential Revision: D43859191
Pulled By: janeyx99
fbshipit-source-id: 702a160ea30e751c8c253c6cf48a05c85361da4d
