fix trt int8 calib precision bug. test=develop (#23036)

paddle/fluid/inference/tensorrt/trt_int8_calibrator.cc

@@ -37,7 +37,8 @@ TRTInt8Calibrator::TRTInt8Calibrator(
     temp_tensor.Resize(data_shape);
     data_tensors_.push_back(temp_tensor);
     data_buffers_[input_name] = std::pair<void*, size_t>(
-        static_cast<void*>(temp_tensor.mutable_data<int16_t>(place)), num_ele);
+        static_cast<void*>(temp_tensor.mutable_data<int16_t>(place)),
+        data_size);
     i += 1;
   }
 }