[Bugfix] Fix DeepEP config for DP4TP4 (#23619)

Signed-off-by: Ming Yang <minos.future@gmail.com>

Author: minosfuture

vllm/model_executor/layers/fused_moe/deepep_ht_prepare_finalize.py

@@ -49,14 +49,14 @@ def topk_indices_dtype(self) -> Optional[torch.dtype]:
         return torch.int64
 
     def _get_dispatch_config(self) -> Optional[deep_ep.Config]:
-        if self.dp_size not in self.available_rank_configs:
+        if self.num_dispatchers_ not in self.available_rank_configs:
             return None
-        return deep_ep.Buffer.get_dispatch_config(self.dp_size)
+        return deep_ep.Buffer.get_dispatch_config(self.num_dispatchers_)
 
     def _get_combine_config(self) -> Optional[deep_ep.Config]:
-        if self.dp_size not in self.available_rank_configs:
+        if self.num_dispatchers_ not in self.available_rank_configs:
             return None
-        return deep_ep.Buffer.get_combine_config(self.dp_size)
+        return deep_ep.Buffer.get_combine_config(self.num_dispatchers_)
 
     def _do_dispatch(
         self,