Add operator to compute the equalization scale (#45096)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/45096
Add operator to compute the equalization scale. This will be used in the integration of equalization into dper int8 fixed quant scheme quantization flow.
Design docs:
https://fb.quip.com/bb7SAGBxPGNC
https://fb.quip.com/PDAOAsgoLfRr
Test Plan: buck test caffe2/caffe2/quantization/server:compute_equalization_scale_test
Reviewed By: jspark1105
Differential Revision: D23779870
fbshipit-source-id: 5e6a8c220935a142ecf8e61100a8c71932afa8d7
