Fix typo
Fix typo

Former-commit-id: 7412fd2d272f0976967ae7ad9de273fc6cda4b6e
chunyang-wen/dynet,xunzhang/dynet,chunyang-wen/dynet,shuheik/dynet,clab/cnn,danielhers/dynet,xunzhang/dynet,shuheik/dynet,shuheik/dynet,danielhers/dynet,clab/dynet,clab/dynet,xunzhang/dynet,danielhers/dynet,shuheik/dynet,clab/cnn,shuheik/dynet,chunyang-wen/dynet,danielhers/dynet,danielhers/dynet,clab/dynet,clab/dynet,clab/cnn,chunyang-wen/dynet,xunzhang/dynet,clab/dynet,danielhers/dynet,shuheik/dynet,clab/dynet,shuheik/dynet,danielhers/dynet,clab/dynet