Fix off_t size detection, so that determined off_t size is 8 instead of 0.

--- configure.orig	Wed Dec 13 11:00:41 2006
+++ configure	Wed Dec 13 11:02:41 2006
@@ -2455,6 +2455,7 @@
   cat > conftest.$ac_ext <<EOF
 #line 2457 "configure"
 #include "confdefs.h"
+#include <sys/types.h>
 #include <stdio.h>
 main()
 {