Drop ascend scheduler

[wangxiyuan]

It's safe to drop ascend scheduler now. The related test and doc has been removed already

• vLLM version: v0.12.0
• vLLM main: https://github.com/vllm-project/vllm/commit/v0.12.0

[gemini-code-assist]

Code Review

This pull request removes the custom ascend_scheduler and its related configurations, making the system fall back to the default vLLM scheduler. The changes primarily consist of deleting code that is no longer necessary. My review identified a critical syntax error in vllm_ascend/platform.py that will prevent the code from running. I have also pointed out a potential logic regression in the same file concerning the configuration of the cache block size, which might lead to incorrect behavior under the default scheduler.

[github-actions]

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[github-actions]

This pull request has conflicts, please resolve those before we can evaluate the pull request.