Remove some Half support in some binary CPU kernels (#33021)
Summary:
They were probably mistakenly added as we do not intend to support Half
on CPUs in general and in these situations Half type would probably be
significantly slower than their float and double counterpart due to the
lack of vectorization and the need of additional casting.
cc XiaobingSuper
Pull Request resolved: https://github.com/pytorch/pytorch/pull/33021
Differential Revision: D19795152
Pulled By: VitalyFedyunin
fbshipit-source-id: b19796db88880a46557e1b2fd06e584d46093562
