lib: replace: snprintf - Fix length calculation for hex/octal 64-bit values.

lib: replace: snprintf - Fix length calculation for hex/octal 64-bit values.

Prevents truncation due to buffer size being too small.

BUG: https://bugzilla.samba.org/show_bug.cgi?id=11947

Signed-off-by: Lorinczy Zsigmond <lzsiga@freemail.c3.hu>
Reviewed-by: Jeremy Allison <jra@samba.org>
Reviewed-by: Michael Adam <obnox@samba.org>
Autobuild-User(master): Michael Adam <obnox@samba.org>
Autobuild-Date(master): Fri Jun  3 03:48:58 CEST 2016 on sn-devel-144