[`Nllb-Moe`] Fix nllb moe accelerate issue (#23758)

fix nllb moe accelerate issue

src/transformers/models/nllb_moe/modeling_nllb_moe.py

@@ -856,7 +856,7 @@ class NllbMoePreTrainedModel(PreTrainedModel):
     config_class = NllbMoeConfig
     base_model_prefix = "model"
     supports_gradient_checkpointing = True
-    _no_split_modules = ["NllbMoeAttention"]
+    _no_split_modules = ["NllbMoeEncoderLayer", "NllbMoeDecoderLayer"]
 
     def _init_weights(self, module):
         """Initialize the weights"""