Revert D25375885: [pytorch][PR] Reenable some BF16 tests on CUDA
Test Plan: revert-hammer
Differential Revision:
D25375885 (https://github.com/pytorch/pytorch/commit/e3893b867fd39cf4f10a129ba9f689eebf10f82b)
Original commit changeset: 2e19fe725ae9
fbshipit-source-id: 69829f3fff4d4a2d1a71bb52e90d3c7f16b27fa3
