[Build] Add support for Ascend950 chip (#7151)

### What this PR does / why we need it?
This PR adds support for the Ascend950 chip. This includes:
- Updating build scripts (`CMakeLists.txt` and `setup.py`) to recognize
the Ascend950 chip and set appropriate compilation flags.
- Disabling a set of custom operators that are not yet supported on the
Ascend950 hardware target.
- Performing a codebase-wide refactoring of `pipe_barrier()` calls to
the namespaced `AscendC::PipeBarrier<>()` for improved code consistency
and adherence to the latest API standards.

Ascend950DT e2e passed (Qwen3-32B-MXFP8) and CI passed
- vLLM version: v0.16.0
- vLLM main:
4034c3d32e
---------
Signed-off-by: linfeng-yuan <1102311262@qq.com>

setup.py

@@ -97,8 +97,10 @@ def get_chip_type() -> str:
                 # A3 case
                 assert npu_name
                 return (chip_name + "_" + npu_name).lower()
+        elif "950" in chip_name:
+            assert npu_name
+            return (chip_name + "_" + npu_name).lower()
         else:
-            # TODO(zzzzwwjj): Currently, A5's chip name has not determined yet.
             raise ValueError(f"Unable to recognize chip name: {chip_name}, please manually set env SOC_VERSION")
     except subprocess.CalledProcessError as e:
         raise RuntimeError(f"Get chip info failed: {e}")
@@ -153,11 +155,14 @@ def gen_build_info():
         "ascend310p3vir02": "_310P",
         "ascend310p3vir04": "_310P",
         "ascend310p3vir08": "_310P",
-        "ascend910_9579": "A5",
     }
-
-    assert soc_version in soc_to_device, f"Undefined soc_version: {soc_version}. Please file an issue to vllm-ascend."
-    device_type = soc_to_device[soc_version]
+    if "ascend950" in soc_version:
+        device_type = "A5"
+    else:
+        assert soc_version in soc_to_device, (
+            f"Undefined soc_version: {soc_version}. Please file an issue to vllm-ascend."
+        )
+        device_type = soc_to_device[soc_version]
 
     package_dir = os.path.join(ROOT_DIR, "vllm_ascend", "_build_info.py")
     with open(package_dir, "w+") as f: