Revert "Port `index.Tensor` to structured kernels."
This reverts commit cfd84125bdb841f0efe038988bb87d645f419338.
Reverted https://github.com/pytorch/pytorch/pull/69607 on behalf of https://github.com/zengk95 due to This is breaking mac trunk tests https://hud.pytorch.org/pytorch/pytorch/commit/cfd84125bdb841f0efe038988bb87d645f419338
