[quant][pt2e] store scale/zero_point as tensor attributes to support serialization (#105894)
Summary:
Currently scale/zero_point for per tensor quant is stored as burnt in literals, this means these values can't be serialized in state_dict, this
PR changes them to buffers/Tensors so that they can be serialized
Test Plan:
python test/test_quantization.py TestQuantizePT2E
Reviewers:
Subscribers:
Tasks:
Tags:
Differential Revision: [D47770963](https://our.internmc.facebook.com/intern/diff/D47770963)
Pull Request resolved: https://github.com/pytorch/pytorch/pull/105894
Approved by: https://github.com/kimishpatel
