Revert "[Functional Collectives] Migrate DeviceMesh::all_reduce to use functional all_reduce. (#95009)"
This reverts commit 0765dbc25ed9368f41225e7de231ee3dd6b188a3.
Reverted https://github.com/pytorch/pytorch/pull/95009 on behalf of https://github.com/jeanschmidt due to this PR is causing internal breakages. Check https://fburl.com/diff/me41urq8
