Kill THLogAdd (#31217)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/31217
It doesn't seem to be used.
Test Plan: Imported from OSS
Differential Revision: D18986642
Pulled By: gchanan
fbshipit-source-id: 96d615df82731d2224d403ab6e2cad6d4c6674fd
