[quant][refactor] Move pattern type definition to ao/quantization/utils.py (#68769)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/68769
att, since we want to use this type in fuser_method_mapping in later PRs
Test Plan:
no change to logic, just regression test on ci
```
python test/test_quantization.py
```
Imported from OSS
Reviewed By: vkuzo
Differential Revision: D32602636
fbshipit-source-id: 15b95241431dfca9b1088d0920bf75705b37aa9a
