lib/replace: Make sure that replacement strto[u]ll does not reset errno unexpectedly

lib/replace: Make sure that replacement strto[u]ll does not reset errno unexpectedly

Fix the replacement functions for strtoll and strtoull to not set errno
to 0 if errno is EINVAL before calling, strto[u]ll does not modify errno
and the base is ok.

Bug: https://bugzilla.samba.org/show_bug.cgi?id=11455

Signed-off-by: Felix Janda <felix.janda@posteo.de>
Reviewed-by: Ralph Boehme <slow@samba.org>
Reviewed-by: Stefan Metzmacher <metze@samba.org>