[P/D] Remove restrictions on mooncake for IPv6 (#5946)

### What this PR does / why we need it?
Remove restrictions on mooncake for IPv6
Dependencies: cann8.5、mooncake v0.3.8.post1

- vLLM version: v0.13.0
- vLLM main:
2c24bc6996

---------

Signed-off-by: liziyu <liziyu16@huawei.com>

vllm_ascend/distributed/kv_transfer/utils/mooncake_transfer_engine.py

@@ -14,14 +14,6 @@ class GlobalTE():
         self.register_buffer_lock = threading.Lock()
 
     def get_transfer_engine(self, hostname: str, device_name: Optional[str]):
-        try:
-            ip = ipaddress.ip_address(hostname)
-            if isinstance(ip, ipaddress.IPv6Address):
-                raise RuntimeError(
-                    "The backend of mooncake's Ascend Direct Xfer Library currently does not support IPv6."
-                )
-        except ValueError:
-            pass
         if self.transfer_engine is None:
             with self.transfer_engine_lock:
                 # Double-Checked Locking