Switch our Android CI to Clang (#26656)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/26656
Updating the NDK to r18 or newer triggers a path in our CI scripts so that we now build with clang instead of gcc.
Google discontinued the gcc support for android quite a while ago, clang is the only way forward.
ghstack-source-id: 90698985
Test Plan: CI
Reviewed By: dreiss
Differential Revision: D17533570
fbshipit-source-id: 5eef4d5a539d8bb1a6682f000d0b5d33b3752819
