[quant] AO migration of the `quant_types.py` (phase 1) (#64916)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/64916
AO Team is migrating the existing torch.quantization into torch.ao.quantization. We are doing it one file at a time to make sure that the internal callsites are updated properly.
This migrates the quant_type.py from torch.quantization to torch.ao.quantization.
At this point both locations will be supported. Eventually the torch.quantization will be deprecated.
Test Plan: `buck test mode/dev //caffe2/test:quantization -- TestAOMigrationQuantization`
Reviewed By: vkuzo
Differential Revision: D30898422
fbshipit-source-id: 3e6126b49f0565a4136d6928cea9eb25368927ff