director: Fixed crash if master_user_separator is set, but we didn't do a proxy lookup. Found by Coverity
director: Fixed crash if master_user_separator is set, but we didn't do a proxy lookup.
Found by Coverity

jwm/dovecot-notmuch,jwm/dovecot-notmuch,jwm/dovecot-notmuch,jwm/dovecot-notmuch,jwm/dovecot-notmuch