remove unused --ninja-global from codegen (#75869)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/75869
ghstack-source-id: 154696012
Test Plan: Verified nothing uses this and relying on CI for confirmation.
Reviewed By: dreiss
Differential Revision: D35674694
fbshipit-source-id: c1d602aa4d85642594160a33606093c33817988f
(cherry picked from commit cac15ca941be298a692570491e96f2db6095e3c1)
