[caffe2] make fused rowwise quant/dequant op work for N-dim tensors (#33426)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/33426
Make 2/4/8-bit fused rowwise conversion operators more general to work for N-dim tensors
Test Plan: CI
Reviewed By: ellie-wen
Differential Revision: D19943136
fbshipit-source-id: 47008544dd7e1d11a346d34f35449e0fcc0e7ee0
