fix segmentation fault in QTensor.choose_qparams_optimized (#85552)
Summary:
Fixes segmentation fault in `QTensor.choose_qparams_optimized`, this
guards against the user passing in a value of `numel` which does not
make sense.
Fixes https://github.com/pytorch/pytorch/issues/85212
Test plan:
Probably not worth it to add a test for this, so testing manually.
```
import torch
input = torch.full((64,), 1, dtype=torch.float32, requires_grad=False)
numel = 1250999896764
n_bins = 0
ratio = 0
bit_width = 0
torch.choose_qparams_optimized(input, numel, n_bins, ratio, bit_width)
// RuntimeError is thrown
```
Pull Request resolved: https://github.com/pytorch/pytorch/pull/85552
Approved by: https://github.com/jerryzh168
