fix batchnorm
fix batchnorm

apache/incubator-singa,nudles/incubator-singa,nudles/incubator-singa,nudles/incubator-singa,apache/incubator-singa,nudles/incubator-singa,nudles/incubator-singa,apache/incubator-singa,apache/incubator-singa,apache/incubator-singa