Remove cases of AT_FORALL_SCALAR_TYPES_EXCEPT_HALF.
Summary: Pull Request resolved: https://github.com/pytorch/pytorch/pull/22890
Test Plan: Imported from OSS
Differential Revision: D16467980
Pulled By: gchanan
fbshipit-source-id: 93ddbd041b7f65cafe8520b095289f14ad6d667f
