[PyTorch] Make SROpFunctor a raw function pointer (#50395)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/50395
There's no need for these to be `std::function`.
ghstack-source-id: 119684828
Test Plan: CI
Reviewed By: hlu1
Differential Revision: D25874187
fbshipit-source-id: e9fa3fbc0dca1219ed13904ca704670ce24f7cc3
