10553 ipadm.1m should document hostmodel property

@@ -404,10 +404,20 @@
                                             (never/passive/active) (TCP).
                      extra_priv_ports       Additional privileged ports
                                             (SCTP/TCP/UDP).
                      forwarding             Packet forwarding (on/off).
                      hoplimit               The IPv6 hoplimit.
+                     hostmodel              IP packet handling on multi-homed
+                                            systems (weak/strong/src-priority)
+                                            (IPv4/IPv6).  weak and strong
+                                            correspond to the model
+                                            definitions defined in RFC 1122.
+                                            src-priority is a hybrid mode
+                                            where outbound packets are sent
+                                            from the interface with the
+                                            packet's source address if
+                                            possible.
                      largest_anon_port      Largest ephemeral port
                                             (SCTP/TCP/UDP).
                      max_buf                Maximum receive or send buffer
                                             size (ICMP/SCTP/TCP/UDP).  This
                                             also sets the upper limit for the