[3/N][Refactor][Quantization]remove packed_modules_mapping from models

[22dimensions]

What this PR does / why we need it?

Some custom models in vllm-ascend define packed_modules_mapping, which prevent keeping same model class with vllm community. So move these custom packed_modules_mapping to quant utils.py. After this pr, some custom models can be removed.

Does this PR introduce any user-facing change?

tested by CI

How was this patch tested?

tested by CI

• vLLM version: v0.10.2
• vLLM main: vllm-project/vllm@5089fd7

[github-actions]

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[gemini-code-assist]

Code Review

This pull request refactors the quantization logic by centralizing the packed_modules_mapping from individual model files into a single dictionary in vllm_ascend/quantization/utils.py. This is a good improvement for maintainability. However, I've found a critical issue where the mapping for the qwen2_5_vl model was removed but not added to the new centralized map, which will likely break quantization for that model. I've also suggested a cleanup in get_quant_method to remove a now-unused parameter, improving code clarity.

[wangxiyuan]

once the model file of qwen3-next and qwen2.5 vl is removed from vllm-ascend, this mapping can be removed as well

cc @wxsIcey please clean this qwen3-next as well.

[wangxiyuan]

Suggested change

	if model_type in packed_modules_model_mapping:
	if model_type in packed_modules_model_mapping.keys():

maybe should be this ?