Revert D26598115: [pytorch][PR] Update XNNPACK
Test Plan: revert-hammer
Differential Revision:
D26598115 (https://github.com/pytorch/pytorch/commit/3721962c33a64946bd3be8ce8c032c4e7d895d22)
Original commit changeset: d652bacdee10
fbshipit-source-id: 7e0128aa9b7691ecd323687da6f6054363b3174a
