[PyTorch] Replace copy_ with data_ptr<float>() since input Tensor's dtype is guaranteed to be float (#67788)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/67788
Based on comments from supriyar in D31657430 (https://github.com/pytorch/pytorch/commit/20aa417e38370d237815d096f98a61ddcdf0f99a).
ghstack-source-id: 142924000
Test Plan: CI
Reviewed By: supriyar
Differential Revision: D32055028
fbshipit-source-id: 756d526585f8ded755ea42b52dbbf5c1687acde2
