fix model config (#50)

* fix model config

* format

Author: Blaizzy

mlx_audio/tts/utils.py

@@ -139,7 +139,14 @@ def load_model(model_path: Path, lazy: bool = False, **kwargs) -> nn.Module:
         weights.update(mx.load(wf))
 
     model_class, model_type = get_model_and_args(model_type=model_type)
-    model_config = model_class.ModelConfig.from_dict(config)
+
+    # Get model config from model class if it exists, otherwise use the config
+    model_config = (
+        model_class.ModelConfig.from_dict(config)
+        if hasattr(model_class, "ModelConfig")
+        else config
+    )
+
     model = model_class.Model(model_config)
     quantization = config.get("quantization", None)
     if quantization is None: