[Model] Add SupportsMultiModal.get_language_model interface (#16007)

Signed-off-by: NickLucche <nlucches@redhat.com>

vllm/model_executor/models/chameleon.py

@@ -988,6 +988,9 @@ class ChameleonForConditionalGeneration(nn.Module, SupportsMultiModal,
             data=self._validate_pixel_values(pixel_values),
         )
 
+    def get_language_model(self) -> torch.nn.Module:
+        return self.model
+
     def get_multimodal_embeddings(
             self, **kwargs: object) -> Optional[MultiModalEmbeddings]:
         image_input = self._parse_and_validate_image_input(**kwargs)