[VLM] Merged multimodal processor for Qwen2-Audio

[DarkLight1337]

Implement #10114 for Qwen2-Audio; also consolidate common code between Ultravox and Qwen2-Audio processing.

I can successfully run the example script with identical results as the previous version of the model.

[github-actions]

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[Isotr0py]

LGTM!