Add placeholder for the `prepare_inputs_for_generation` method for compatibility with transformers>=4.50

modeling_phi4mm.py

@@ -1932,6 +1932,15 @@ class Phi4MMModel(Phi4MMPreTrainedModel):
                 )
         return causal_mask
 
+    def prepare_inputs_for_generation():
+        """
+        Placeholder for the `prepare_inputs_for_generation` method.
+
+        This function is part of the `GenerationMixin` and is added to the `Phi4MMModel`
+        class to prevent the model from breaking due to the AttributeError.
+        """
+        pass
+
 
 class Phi4MMForCausalLM(Phi4MMPreTrainedModel, GenerationMixin):
     _tied_weights_keys = ["lm_head.weight"]