Windows - suppress nonsensical(for this OS) system check.

Amends 48141f3c

cmake/os/WindowsCache.cmake

@@ -90,6 +90,7 @@ SET(HAVE_LRAND48 CACHE  INTERNAL "")
 SET(HAVE_LSTAT CACHE  INTERNAL "")
 SET(HAVE_MADVISE CACHE  INTERNAL "")
 SET(HAVE_MALLINFO CACHE  INTERNAL "")
+SET(HAVE_MALLINFO2 CACHE  INTERNAL "")
 SET(HAVE_MALLOC_H 1 CACHE  INTERNAL "")
 SET(HAVE_MEMALIGN CACHE  INTERNAL "")
 SET(HAVE_MEMCPY 1 CACHE  INTERNAL "")