SmartOS: permanently set VNC port

vmadm update dece98e8-29d7-4394-8cf1-d0185e2258b7 vnc_port=35351

...
  "vnc": {
    "host": "192.168.0.40",
    "port": 35351,
    "display": 29451
  },
...

Now, you can configure remmina to connect to 192.168.0.40:35351