【bugfix】fix connector register failed (#3335)

### What this PR does / why we need it?
Register the connector in the plugin
### Does this PR introduce _any_ user-facing change?

### How was this patch tested?


- vLLM version: v0.11.0rc3
- vLLM main: https://github.com/vllm-project/vllm/commit/v0.11.0

---------

Signed-off-by: fems14 <1804143737@qq.com>

setup.py

@@ -391,7 +391,9 @@ setup(
     extras_require={},
     entry_points={
         "vllm.platform_plugins": ["ascend = vllm_ascend:register"],
-        "vllm.general_plugins":
-        ["ascend_enhanced_model = vllm_ascend:register_model"],
+        "vllm.general_plugins": [
+            "ascend_enhanced_model = vllm_ascend:register_model",
+            "ascend_kv_connector = vllm_ascend:register_connector"
+        ],
     },
 )