[bugfix] some bugs maybe fail to run (#896)

### What this PR does / why we need it?
Solve the bug that the graph mode is the same as p and d, and some other
bugs.
### Does this PR introduce _any_ user-facing change?
Wouldn't be
### How was this patch tested?
Follow the end-to-end test

Signed-off-by: ningbenzhe1 <ningbenzhe@huawei.com>

vllm_ascend/distributed/parallel_state.py

@@ -21,12 +21,18 @@ def get_etp_group() -> GroupCoordinator:
     return _ETP
 
 
+def model_parallel_initialized():
+    return (_ETP is not None and _EP is not None)
+
+
 def init_ascend_model_parallel(
     expert_parallel_size: int = 1,
     expert_tensor_parallel_size: int = 1,
     world_size: Optional[int] = None,
     backend: Optional[str] = None,
 ):
+    if model_parallel_initialized():
+        return
     assert torch.distributed.is_initialized()
     world_size = world_size or torch.distributed.get_world_size()
     backend = backend or torch.distributed.get_backend(