clean pipeline question_answering. (#36986)

Signed-off-by: zhanluxianshen <[email protected]>

Author: zhanluxianshen

src/transformers/pipelines/question_answering.py

@@ -340,7 +340,6 @@ def _sanitize_parameters(
         if max_answer_len is not None:
             if max_answer_len < 1:
                 raise ValueError(f"max_answer_len parameter should be >= 1 (got {max_answer_len}")
-        if max_answer_len is not None:
             postprocess_params["max_answer_len"] = max_answer_len
         if handle_impossible_answer is not None:
             postprocess_params["handle_impossible_answer"] = handle_impossible_answer
@@ -542,11 +541,9 @@ def postprocess(
         for output in model_outputs:
             if self.framework == "pt" and output["start"].dtype == torch.bfloat16:
                 start_ = output["start"].to(torch.float32)
-            else:
-                start_ = output["start"]
-            if self.framework == "pt" and output["start"].dtype == torch.bfloat16:
                 end_ = output["end"].to(torch.float32)
             else:
+                start_ = output["start"]
                 end_ = output["end"]
             example = output["example"]
             p_mask = output["p_mask"]