[WIP] Layernorm Fake FP16 Op. (#39103)
Summary:
hyuen
I have added few changes to the LayerNorm Fake FP16 op.
Test case: test_layernorm_nnpi_fp16.py
Pull Request resolved: https://github.com/pytorch/pytorch/pull/39103
Reviewed By: hl475
Differential Revision: D21768096
Pulled By: hyuen
fbshipit-source-id: 9bb7a5f759d783149b599706ff8d285653715f01
