[Misc] Code clean up

[wangxiyuan]

1. move attention mask builder from v0 to common place.
2. remove some useless function
3. clean up model_runner_v1

• vLLM version: v0.9.1
• vLLM main: vllm-project/vllm@d2e841a

[codecov]

Codecov Report

Attention: Patch coverage is 97.75281% with 2 lines in your changes missing coverage. Please review.

Project coverage is 54.50%. Comparing base (c30ddb8) to head (e65fcea).
Report is 88 commits behind head on main.

Files with missing lines	Patch %	Lines
vllm_ascend/attention/attention.py	50.00%	1 Missing ⚠️
vllm_ascend/attention/attention_mask.py	97.82%	1 Missing ⚠️

❌ Your patch check has failed because the patch coverage (97.75%) is below the target coverage (100.00%). You can increase the patch coverage or adjust the target coverage.

Additional details and impacted files

@@             Coverage Diff             @@
##             main    #1630       +/-   ##
===========================================
+ Coverage   27.39%   54.50%   +27.10%     
===========================================
  Files          56       82       +26     
  Lines        6191    10001     +3810     
===========================================
+ Hits         1696     5451     +3755     
- Misses       4495     4550       +55     

Flag	Coverage Δ
unittests	54.50% <97.75%> (+27.10%)	⬆️

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[wangxiyuan]

@Yikun @ganyi1996ppo @jianzs please help review. Thanks. This PR is mainly for clear code maintainance

[github-actions]

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