Remove unused cuBLAS driver functions for getrs (#23375)
Summary:
Changelog:
- Remove getrs driver functions from THCBlas{.h/.cpp}
Pull Request resolved: https://github.com/pytorch/pytorch/pull/23375
Test Plan: - Build to pass to confirm no callsites were missed.
Differential Revision: D16539079
Pulled By: soumith
fbshipit-source-id: b5c285a2d36714ddf3393337eec7d85b1eaf3f51
