Back out "[pytorch][PR] [ONNX] Add eliminate_unused_items pass"
Summary:
Original commit changeset: 30e1a6e8823a
cause issue to fusing BN
Test Plan: revert
Reviewed By: houseroad
Differential Revision: D22296958
fbshipit-source-id: 62664cc77baa8811ad6ecce9d0520a2ab7f89868
