Enabled dropout removal pass in mobile optimizer. (#38254)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/38254
ghstack-source-id: 103939143
Test Plan:
mobile optimizer test.
Also tested on pytext model.
Reviewed By: dreiss
Differential Revision: D21505862
fbshipit-source-id: 95c3b205e85cc7c4f20f5416c09cd0bc862849ce
