Added Operator_Schema's for missing FakeFP16 Operators (#39363)
Summary:
Added Operator_Schema's for missing FakeFP16 Operators
Reviewer: hyz
Pull Request resolved: https://github.com/pytorch/pytorch/pull/39363
Differential Revision: D21885816
Pulled By: hyuen
fbshipit-source-id: aa6abd984df40660ab59a37c9898fbac430866da
