[Misc] Clean up useless code

[wangxiyuan]

Essential Elements of an Effective PR Description Checklist

• The purpose of the PR, such as "Fix some issue (link existing issues this PR will resolve)".
• The test plan, such as providing test command.
• The test results, such as pasting the results comparison before and after, or e2e results
• (Optional) The necessary documentation update, such as updating supported_models.md and examples for a new model.

Purpose

Clean up the useless code in config.py

Test Plan

Just a code clean up, no need for test update

Test Result

(Optional) Documentation Update

[github-actions]

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[gemini-code-assist]

Summary of Changes

Hello @wangxiyuan, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request is a targeted code hygiene effort, removing an identified section of unreachable code from vllm/config.py. The change specifically targets a conditional block that would never execute, thereby improving the codebase's clarity and maintainability without introducing any functional changes or altering existing behavior.

Highlights

• Code Cleanup: Removed a block of dead code in vllm/config.py within the __post_init__ method. This code was part of a conditional check for ray_only_devices that would never evaluate to true, rendering the associated logic unreachable.

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[gemini-code-assist]

Code Review

This pull request removes a block of dead code from the ParallelConfig.__post_init__ method in vllm/config.py.

The removed code initialized a list ray_only_devices as empty and then checked if current_platform.device_type was present in this empty list. Since this condition would always be false, the subsequent logic to set self.distributed_executor_backend to "ray" or raise a ValueError was unreachable.

The removal is correct and improves code clarity and maintainability by eliminating this unused logic. The local import of current_platform within the removed block was also redundant, as current_platform is already imported at the module level and available in the __post_init__ scope.

This change is a good cleanup and has no impact on existing functionality.