Add a sample mixerctl.conf(5).

Pretty terse for now but will eventually come with some more complex
examples when ratchov@ finishes some ongoing work on aucat(1).
ok ratchov@ jmc@ deraadt@

src/etc/Makefile

@@ -1,4 +1,4 @@
-#	$OpenBSD: Makefile,v 1.310 2011/10/06 20:49:25 deraadt Exp $
+#	$OpenBSD: Makefile,v 1.311 2011/10/29 14:29:33 ajacoutot Exp $
 
 TZDIR=		/usr/share/zoneinfo
 LOCALTIME=	Canada/Mountain
@@ -37,7 +37,7 @@ BIN1=	changelist csh.cshrc csh.login csh.logout daily dhcpd.conf \
 	rbootd.conf rc rc.conf rc.local rc.securelevel rc.shutdown \
 	remote rpc services shells syslog.conf weekly \
 	etc.${MACHINE}/disktab dhclient.conf mailer.conf ntpd.conf \
-	moduli pf.os sensorsd.conf ifstated.conf
+	moduli pf.os sensorsd.conf ifstated.conf mixerctl.conf
 
 .if ${MACHINE} != "aviion" && ${MACHINE} != "mvme68k" && \
     ${MACHINE} != "mvme88k"

src/etc/mixerctl.conf

@@ -0,0 +1,7 @@
+# $OpenBSD: mixerctl.conf,v 1.1 2011/10/29 14:29:33 ajacoutot Exp $
+#
+# mixerctl(1) configurable parameters. See mixerctl.conf(5) for details.
+#
+
+# output volume value for most audio cards
+#outputs.master=200