fix lint

JiayiFeng · JiayiFeng · commit a122dcccd553 · 2018-04-04T14:26:01.000+08:00
diff --git a/paddle/fluid/operators/reader/create_double_buffer_reader_op.cc b/paddle/fluid/operators/reader/create_double_buffer_reader_op.cc
@@ -13,6 +13,7 @@
 // limitations under the License.
 
 #include <thread>  //NOLINT
+
 #include "paddle/fluid/framework/channel.h"
 #include "paddle/fluid/operators/reader/reader_op_registry.h"
 
