[ONNX] Update ONNX export of torch.where to support ByteTensor as input. (#42264)
Summary:
`torch.where` supports `ByteTensor` and `BoolTensor` types for the first input argument (`condition` predicate). Currently, ONNX exporter assumes that the first argument is `BoolTensor`. This PR updates the export for `torch.where` to correctly support export when first argument is a `ByteTensor`.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/42264
Reviewed By: houseroad
Differential Revision: D22968473
Pulled By: bzinodev
fbshipit-source-id: 7306388c8446ef3faeb86dc89d72d1f72c1c2314
