When savecore can't find a core dump, it reports something like
ls: cannot access core.*: No such file or directory
to stderr, and fails. If privlog is set, it also mails out a "Could
not save core dump" note.
Suppress the error message, and mail out "Could not find core dump to
save" instead.
Signed-off-by: Markus Armbruster <armbru@pond.sub.org>
