update create_optimizer for updated api

src/axolotl/core/trainers/mixins/optimizer.py

@@ -104,7 +104,7 @@ class OptimizerMixin(Trainer):
 
         return optimizer_grouped_parameters
 
-    def create_optimizer(self):
+    def create_optimizer(self, model=None):
         if (
             self.args.loraplus_lr_ratio is None
             and self.args.embedding_lr_scale is None
@@ -112,9 +112,9 @@ class OptimizerMixin(Trainer):
             and self.args.lr_groups is None
             and self.optimizer_cls_and_kwargs is None
         ):
-            return super().create_optimizer()
+            return super().create_optimizer(model=model)
 
-        opt_model = self.model_wrapped if is_sagemaker_mp_enabled() else self.model
+        opt_model = self.model if model is None else model
 
         if (
             not self.optimizer