dbr quant: initial support of qconfig_dict for modules (#69719)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/69719
This PR changes the API signature of DBR quant to use `qconfig_dict`,
similar to FX graph mode quantization. In this first PR, only basic
functionality is implemented:
* qconfig=None or static quantization with quint8 only is tested
* non-default qconfig for modules only is tested
* targeting ops by order is not implemented
Expanding this support will be done in future PRs.
Test Plan:
```
python test/test_quantization.py TestQuantizeDBR
```
Reviewed By: jerryzh168
Differential Revision: D33003475
Pulled By: vkuzo
fbshipit-source-id: f5af81e29c34ea57c2e23333650e44e1758102e4
