change model output parameter to last_hidden_states

Author: jiqing-feng

optimum/intel/ipex/modeling_base.py

@@ -282,7 +282,7 @@ def forward(
             inputs["attention_mask"] = attention_mask
 
         outputs = self._call_model(**inputs)
-        return ModelOutput(**outputs) if isinstance(outputs, dict) else ModelOutput(logits=outputs[0])
+        return ModelOutput(**outputs) if isinstance(outputs, dict) else ModelOutput(last_hidden_state=outputs[0])
 
 
 class IPEXModelForQuestionAnswering(IPEXModel):