[caffe2][quantization] Add initializer and precision as read-only property to QueryTensorQparam (#34706)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/34706
as title
Test Plan: test in stacked diff
Reviewed By: csummersea
Differential Revision: D20436618
fbshipit-source-id: e51ef0a22708425cd296c05f4089fe8c98eda90a
