[quant][core][feature] Implement masked_fill for CUDA tensors (#85108)
Summary:
- Add new cuda test for masked_fill
- Add in QuantizedCUDA implementation for masked_fill
Test Plan:
```
python test/test_quantization.py -k test_qtensor_masked_fill_cuda
```
Reviewers: dzdang
Subscribers:
Tasks: Fixes https://github.com/pytorch/pytorch/issues/83110
Tags: quant
Pull Request resolved: https://github.com/pytorch/pytorch/pull/85108
Approved by: https://github.com/dzdang
