Fixed behavior if missing library cudnn.lib

AlexeyAB

2017-01-16 d7a30ada7e82daf7ce5ca91acac15c1723188fc5

 src/convolutional_layer.c

@@ -8,6 +8,10 @@
#include <stdio.h>
#include <time.h>

#ifdef CUDNN
#pragma comment(lib, "cudnn.lib")  
#endif

#ifdef AI2
#include "xnor_layer.h"
#endif