[quant][fx][graphmode][refactor] Factor out generate_qconfig_map to qconfig_utils.py (#58453)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/58453
Move the class method generate_qconfig_map to qconfig_utils, will add more PRs
to remove functions out of Quantizer and eventually remove the Quantizer object
Test Plan:
python test/test_quantization.py TestQuantizeFx
python test/test_quantization.py TestQuantizeFxOps
Imported from OSS
Reviewed By: vkuzo
Differential Revision: D28497965
fbshipit-source-id: 3c78cfe676965d20a8834a859ffed4d8e9ecade4