Enable to use custom tracer in FX `symbolic_trace` (#23105)

* Enable to use custom tracer in FX `symbolic_trace`

* Integrate feedback from review

* Formatting
Co-authored-by: Sylvain Gugger <35901082+sgugger@users.noreply.github.com>

---------
Co-authored-by: Sylvain Gugger <35901082+sgugger@users.noreply.github.com>

src/transformers/utils/fx.py

@@ -1207,6 +1207,7 @@ def symbolic_trace(
     model: PreTrainedModel,
     input_names: Optional[List[str]] = None,
     disable_check: bool = False,
+    tracer_cls: Type[HFTracer] = HFTracer,
 ) -> GraphModule:
     """
     Performs symbolic tracing on the model.
@@ -1218,6 +1219,8 @@ def symbolic_trace(
             The names of the inputs of the traced model. If unset, model.dummy_inputs.keys() are used instead.
         disable_check (`bool`, *optional*, defaults to `False`):
             If `True`, no check is done before trying to trace the model, this is mostly usesul for debugging purposes.
+        tracer_cls (`Type[HFTracer]`, *optional*, defaults to `HFTracer`):
+            The tracer class to use for instantiating the tracer. If unset, `HFTracer` is used instead.
 
     Returns:
         `torch.fx.GraphModule`: A GraphModule constructed by recording operations seen while tracing the model.
@@ -1240,7 +1243,7 @@ def symbolic_trace(
         check_if_model_is_supported(model)
 
     # Tracing.
-    tracer = HFTracer()
+    tracer = tracer_cls()
     traced_graph = tracer.trace(model, concrete_args=concrete_args)
     traced = torch.fx.GraphModule(model, traced_graph)