pytorch

f9d07ae6 - Update torch::lazy::BackendDevice to have a new default ordinal (#76264)

Update torch::lazy::BackendDevice to have a new default ordinal (#76264) Summary: Fixes https://github.com/pytorch/xla/issues/3490. Updates `torch::lazy::BackendDevice` with changes below: 1. Remove the no-op string constructor. 2. Update default ordinal to `-1`. 3. Add a `is_valid` function to check if `ordinal` is valid/non-default (`ordinal >= 0`). Pull Request resolved: https://github.com/pytorch/pytorch/pull/76264 Reviewed By: mrshenli Differential Revision: D35860266 Pulled By: alanwaketan fbshipit-source-id: 554ebe16a0683d37b00270c4f35163bf690bfe28 (cherry picked from commit b941d10e8545dfecfb34e4d5c24a29a1cc49bc4b)