fix args (#996)

Author: Jintao-Huang

swift/llm/utils/argument.py

@@ -1285,7 +1285,7 @@ def __post_init__(self):
             self.merge_device_map = 'cpu' if self.quant_bits != 0 else 'auto'
         if self.quant_bits > 0 and self.dtype == 'AUTO':
             self.dtype = 'fp16'
-            logger.info(f'Setting args.dtype: {args.dtype}')
+            logger.info(f'Setting args.dtype: {self.dtype}')
         super().__post_init__()
         if len(self.dataset) == 0 and self.quant_bits > 0:
             self.dataset = ['alpaca-zh#10000', 'alpaca-en#10000']