[iOS GPU][Perf][2/n] Prepack linear + Fuse relu/hardtanh (#57665)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/57665
Prepacking linear weights in JIT passes gives us 25% win on mobilenetv2.
ghstack-source-id: 128338535
allow-large-files
Test Plan: - CI
Reviewed By: kimishpatel
Differential Revision: D28033081
fbshipit-source-id: b006313f6b94b31b8d7ddacc0165ceab5a23dce9
