[MTP]Support mtp reshard (#4099)

* support rl reshard

* modify model name

fastdeploy/config.py

@@ -134,6 +134,7 @@ class ModelConfig:
         self.lm_head_fp32: bool = False
         self.model_format = "auto"
         self.partial_rotary_factor: float = 1.0
+        self.num_nextn_predict_layers = 0
         for key, value in args.items():
             if hasattr(self, key) and value != "None":
                 setattr(self, key, value)