update default config to new grammar

ok eric@

src/etc/mail/smtpd.conf

@@ -1,4 +1,4 @@
-#	$OpenBSD: smtpd.conf,v 1.9 2016/05/03 18:43:45 jung Exp $
+#	$OpenBSD: smtpd.conf,v 1.10 2018/05/24 11:40:17 gilles Exp $
 
 # This is the smtpd server system-wide configuration file.
 # See smtpd.conf(5) for more information.
@@ -9,8 +9,11 @@ table aliases file:/etc/mail/aliases
 #
 listen on lo0
 
+action "local" mbox alias <aliases>
+action "relay" relay
+
 # Uncomment the following to accept external mail for domain "example.org"
 #
-# accept from any for domain "example.org" alias <aliases> deliver to mbox
-accept for local alias <aliases> deliver to mbox
-accept from local for any relay
+# match from any for domain "example.org" action "local"
+match for local action "local"
+match from local for any action "relay"