fx quant: remove FixedQParamsOpQuantizeHandler from quantize.py (#57393)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/57393
Moves the information on whether we should pass the information
whether the output is quantized based on the inputs to live
on the qhandler object. This allows us to remove
FixedQParamsOpQuantizeHandler from quantize.py, further reducing
the coupling between handler objects and the quantization pass.
Test Plan:
```
python test/test_quantization.py TestQuantizeFxOps
```
Imported from OSS
Reviewed By: astaff
Differential Revision: D28132414
fbshipit-source-id: 5c28524b47c00f618d3a38657376abae9e6ffe7c