Mention -p's address argument in manpage synopsis

--HG--
extra : convert_revision : abef8fc8584889de6fd92ceaec28d094419462e0

dropbear.8

@@ -7,7 +7,7 @@ dropbear \- lightweight SSH2 server
 .I banner\fR] [\-d
 .I dsskey\fR] [\-r
 .I rsakey\fR] [\-p
-.IR port ]
+.IR [address:]port ]
 .SH DESCRIPTION
 .B dropbear
 is a SSH 2 server designed to be small enough to be used in small memory