[Release]Update release note (#1753)

There is still issue with pp in some case. such as aclgraph, ray. Remove
the related doc in release note

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

Author: wangxiyuan

docs/source/user_guide/release_notes.md

@@ -8,7 +8,6 @@ This is the 1st release candidate of v0.9.2 for vLLM Ascend. Please follow the [
 - Pooling model works with V1 engine now. You can take a try with Qwen3 embedding model [#1359](https://github.com/vllm-project/vllm-ascend/pull/1359).
 - The performance on Atlas 300I series has been improved. [#1591](https://github.com/vllm-project/vllm-ascend/pull/1591)
 - aclgraph mode works with Moe models now. Currently, only Qwen3 Moe is well tested. [#1381](https://github.com/vllm-project/vllm-ascend/pull/1381)
-- Pipeline parallelism works with V1 Engine now. [#1700](https://github.com/vllm-project/vllm-ascend/pull/1700)
 
 ### Core
 - Ascend PyTorch adapter (torch_npu) has been upgraded to `2.5.1.post1.dev20250619`. Don’t forget to update it in your environment. [#1347](https://github.com/vllm-project/vllm-ascend/pull/1347)
@@ -28,9 +27,6 @@ This is the 1st release candidate of v0.9.2 for vLLM Ascend. Please follow the [
 - DeepSeek now works with prefix cache now. [#1498](https://github.com/vllm-project/vllm-ascend/pull/1498)
 - Support prompt logprobs to recover ceval accuracy in V1 [#1483](https://github.com/vllm-project/vllm-ascend/pull/1483)
 
-### Known Issues
-- Pipeline parallelism is not working on ray in this version. It'll be supported in the next release. [#1751](https://github.com/vllm-project/vllm-ascend/issues/1751)
-
 ## v0.9.1rc1 - 2025.06.22
 
 This is the 1st release candidate of v0.9.1 for vLLM Ascend. Please follow the [official doc](https://vllm-ascend.readthedocs.io/en/) to get started.