Fix commandhelper build on win32

For win32 we need EXIT_AM_SKIP which is in testutils.h. We must
define NO_LIBVIRT to prevent replacement of fprintf with
virFilePrintf as we can't link to libvirt_util.la
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

tests/commandhelper.c

@@ -28,6 +28,8 @@
 #include <sys/stat.h>
 
 #include "internal.h"
+#define NO_LIBVIRT
+#include "testutils.h"
 
 #ifndef WIN32