lib-auth: Don't crash in auth_master_*() lookups if caller hasn't created ioloop.
lib-auth: Don't crash in auth_master_*() lookups if caller hasn't created ioloop.

LTD-Beget/dovecot,LTD-Beget/dovecot,LTD-Beget/dovecot,LTD-Beget/dovecot,LTD-Beget/dovecot