[quant][bug fix] Fix qrange_len in `torch.ao.quantization.utils.py` (#95297)
Summary:
It looks like there is a typo and qrange_len should be 2^32 instead of 2^31, as it is currently set.
Test Plan:
```
python test/test_quantization.py TestObserver.test_per_tensor_observers
```
Reviewers:
Subscribers:
Tasks: https://github.com/pytorch/pytorch/issues/95295
Tags:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/95297
Approved by: https://github.com/vkuzo
