Revert D28461013: [nnc] Enable CPU fusion inside Facebook, take 2
Test Plan: revert-hammer
Differential Revision:
D28461013 (https://github.com/pytorch/pytorch/commit/c76405d3b1685a4ae0c3fd76d8d69199b340f83a)
Original commit changeset: 79a80b6ffb65
fbshipit-source-id: d9cc5c512542153f39664635fb080d797a9de7d0
