Revert "[cherry-pick][refactor]support gatingtopk operator generalization (#4050)"

[wangxiyuan]

This reverts commit c87a77e.

it breaks ops e2e test

[github-actions]

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[gemini-code-assist]

Code Review

This pull request reverts a previous change that generalized the gatingtopk operator, which was found to break end-to-end tests. The revert restores the previous, more specific implementation across vllm_ascend/ops/moe/experts_selector.py and related tests. The changes appear to correctly revert the problematic commit. I have one suggestion on the restored code in experts_selector.py to improve its robustness and prevent a potential bug where logic blocks could unintentionally overwrite each other.

[gemini-code-assist]

The if statement on this line could potentially conflict with the preceding if is_deepseek_v3_r1: block. If conditions for both blocks are met (e.g., for a deepseek_v3_r1 model with scoring_func="softmax"), the results from the first block will be overwritten. This could lead to incorrect expert selection. Using elif would make these conditions mutually exclusive and prevent this potential bug.

Suggested change

	if not use_grouped_topk and custom_routing_function is None and scoring_func == "softmax":
	elif not use_grouped_topk and custom_routing_function is None and scoring_func == "softmax":

[wangxiyuan]

ops test should be updated

    def is_vl_model(vllm_config: VllmConfig):
        """Checks if the model is a VL model by config"""
        global _IS_VL_MODEL
        if _IS_VL_MODEL is None:
>           model_configs = vllm_config.model_config.hf_config.to_dict()
                            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
E           AttributeError: 'NoneType' object has no attribute 'hf_config'