Fix CUDNN to work with Windows.
Fix CUDNN to work with Windows.


Former-commit-id: 8fe7a24a4cfe7d02fc4fed996a3c9c3fbb62ef98
shuheik/dynet,clab/cnn,chunyang-wen/dynet,clab/dynet,danielhers/dynet,danielhers/dynet,chunyang-wen/dynet,shuheik/dynet,xunzhang/dynet,chunyang-wen/dynet,danielhers/dynet,clab/dynet,chunyang-wen/dynet,danielhers/dynet,clab/dynet,xunzhang/dynet,danielhers/dynet,clab/dynet,shuheik/dynet,shuheik/dynet,clab/dynet,danielhers/dynet,clab/cnn,xunzhang/dynet,clab/dynet,clab/dynet,clab/cnn,xunzhang/dynet,shuheik/dynet,shuheik/dynet,shuheik/dynet,danielhers/dynet