Revert "[ONNX] Add quantization support to _avg_pool opset 9 and clean up (#79793)"
This reverts commit 356341a3ec322357d9a523f31ebb2933a426a026.
Reverted https://github.com/pytorch/pytorch/pull/79793 on behalf of https://github.com/malfet due to Broke trunk, see https://hud.pytorch.org/pytorch/pytorch/commit/356341a3ec322357d9a523f31ebb2933a426a026
