[Chore]: Remove HF format Phi4-MM examples

[Isotr0py]

Purpose

• Remove HF phi-4-multimodal example missed in Delete HF version of Phi 4 MM #30049

Test Plan

Test Result

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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.
• (Optional) Release notes update. If your change is user facing, please update the release notes draft in the Google Doc.

[mergify]

Documentation preview: https://vllm--31405.org.readthedocs.build/en/31405/

[gemini-code-assist]

Code Review

This pull request correctly removes the deprecated phi4_multimodal example code from audio_language.py, vision_language.py, and vision_language_multi_image.py. The changes consist of straightforward deletions of the relevant functions and their corresponding entries in the model maps. These removals are consistent across all affected files and align with the PR's stated purpose. The changes are clean and I see no issues.