Fix mistral config (#29172)

Signed-off-by: Julien Denize <julien.denize@mistral.ai>
Signed-off-by: Julien Denize <40604584+juliendenize@users.noreply.github.com>
Co-authored-by: gemini-code-assist[bot] <176961590+gemini-code-assist[bot]@users.noreply.github.com>
Co-authored-by: Patrick von Platen <patrick.v.platen@gmail.com>

vllm/transformers_utils/configs/mistral.py

@@ -90,6 +90,10 @@ def _remap_mistral_yarn_args(config: dict) -> dict:
         "rope_type": "yarn",
         "mscale_all_dim": 1,
     }
+
+    if rope_theta := config.pop("rope_theta", None):
+        config["rope_parameters"]["rope_theta"] = rope_theta
+
     for old_name, new_name in yarn_config_map.items():
         if old_name in yarn_config:
             config["rope_parameters"][new_name] = yarn_config.pop(old_name)