Revert D31325860: [PyTorch] Implement improved version of gather_ranges_to_dense
Test Plan: revert-hammer
Differential Revision:
D31325860 (https://github.com/pytorch/pytorch/commit/23710e2d807750c94bbf61a3199472885de147c7)
Original commit changeset: 8e154f929ff7
fbshipit-source-id: 6d36d50d6bd4ec4fe07a6e2d1d0110504b9c8b53
