Removed dead code from THTensorMath.h (#17873)
Summary:
This PR removes dead code from THTensorMath.h
I found these unused methods while working on a PR where i plan to move fill and zero methods from TH/THC to Aten.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/17873
Differential Revision: D14407013
Pulled By: izdeby
fbshipit-source-id: a3551c5d91e7b380931a8b3bd4b3ae972d16911d
