util: Fix a signed/unsigned comparison
[107/390] Compiling lib/util/time.c
../../../lib/util/time.c: In function ‘timespec_string_buf’:
../../../lib/util/time.c:416:10: warning: comparison of integer expressions of different signedness: ‘size_t’ {aka ‘long unsigned int’} and ‘int’ [-Wsign-compare]
416 | if (len == -1) {
| ^~
Signed-off-by: Martin Schwenke <martin@meltin.net>
Reviewed-by: Volker Lendecke <vl@samba.org>
Autobuild-User(master): Volker Lendecke <vl@samba.org>
Autobuild-Date(master): Thu Jul 16 04:00:52 UTC 2020 on sn-devel-184