Add hf_GPT2_generate and hf_T5_generate (#1625)
Summary:
Signed-off-by: Edward Z. Yang <ezyang@meta.com>
Pull Request resolved: https://github.com/pytorch/benchmark/pull/1625
Reviewed By: xuzhao9
Differential Revision: D45693443
Pulled By: ezyang
fbshipit-source-id: 6e4eb01b2e365d729862133d0a093c457c558ec4
