unbreak compilation

modules/gui/skins2/unzip/ioapi.c

@@ -6,6 +6,9 @@
    Copyright (C) 1998-2005 Gilles Vollant
 */
 
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
 
 #include "zlib.h"
 #include "ioapi.h"