fix: Ensure device consistency in OneFormerProcessor outputs Fixes #42722
Author: nathon-lee
Pull request: yes
Labels: name: Code agent slop

fix #42722

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Fixes # (issue)


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Comments:
**[For maintainers]** Suggested jobs to run (before merge)

run-slow: oneformer

View the CircleCI Test Summary for this PR:

https://huggingface.co/spaces/transformers-community/circle-ci-viz?pr=42858&sha=ccb6eb