Revert D32611368: [pytorch][PR] Initial version of general convolution_backward
Test Plan: revert-hammer
Differential Revision:
D32611368 (https://github.com/pytorch/pytorch/commit/445b31abff8bfdbd6e74acc420585089e95ef585)
Original commit changeset: 26d759b7c908
fbshipit-source-id: e91f45f0f31150e60d657a3964b7e42027beff58
