fix multimodal model's register

Author: lizhenyun01

fastdeploy/entrypoints/llm.py

@@ -75,9 +75,8 @@ def __init__(
         enable_logprob: Optional[bool] = False,
         **kwargs,
     ):
-        deprecated_kwargs_warning(**kwargs)
-
         load_model_register_plugins()
+        deprecated_kwargs_warning(**kwargs)
         model = retrive_model_from_server(model, revision)
         engine_args = EngineArgs(
             model=model,