Add /etc/hotplug.

ok millert@

src/etc/mtree/4.4BSD.dist

@@ -1,4 +1,4 @@
-#	$OpenBSD: 4.4BSD.dist,v 1.165 2004/05/03 15:18:19 drahn Exp $
+#	$OpenBSD: 4.4BSD.dist,v 1.166 2004/06/05 18:26:28 grange Exp $
 
 /set type=dir uname=root gname=wheel mode=0755
 # .
@@ -43,6 +43,11 @@ disklabels
 # ./etc/disklabels
 ..
 
+# ./etc/hotplug
+hotplug
+# ./etc/hotplug
+..
+
 # ./etc/isakmpd
 isakmpd