[qunat][graphmode][fx] Add a separate lower_to_native_backend function for relu (#62861)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/62861
This PR adds a lower_to_native_backend function to lower a quantized reference model
to a model that uses fbgemm/qnnpack ops. We'll gradually add support and remove
the fbgemm/qnnpack specific handling in quantization_patterns.py
Test Plan:
python test/test_quantization.py TestQuantizeFx
python test/test_quantization.py TestQuantizeFxOps
Imported from OSS
Reviewed By: vkuzo
Differential Revision: D30165828
fbshipit-source-id: de1149cd7e7c1840c17c251cd4d35004afd015b7
