[Misc] Refactor additional_config (#1029)

More and more config options are added to additional_config. This PR
provide a new AscendConfig to manage these config options by an easier
way to make code cleaner and readable.

 This PR also added the `additional_config` doc for users.

Added the test_ascend_config.py to make sure the new AscendConfig works
as expect.

TODO: Add e2e test with torchair and deepseek once the CI resource is
available.

Signed-off-by: wangxiyuan <wangxiyuan1007@gmail.com>

tests/multicard/test_dynamic_npugraph_batchsize.py

@@ -18,8 +18,6 @@ import pytest
 import torch
 from vllm import LLM, SamplingParams
 
-from vllm_ascend.utils import vllm_version_is
-
 MODELS = [
     "Qwen/Qwen2.5-0.5B-Instruct",
 ]
@@ -32,9 +30,6 @@ prompts = [
 ]
 
 
-@pytest.mark.skipif(
-    (vllm_version_is("0.8.5") or vllm_version_is("0.8.5.post1")),
-    reason="aclgraph not supported in v0.8.5 and v0.8.5.post1")
 @pytest.mark.parametrize("model", MODELS)
 @pytest.mark.parametrize("tp_size", TENSOR_PARALLELS)
 @pytest.mark.parametrize("max_tokens", [64])