Summary

Add support for dhcp option 138 (RFC-5417 - CAPWAP AC)

Use case

Option 138 is used widely to inform WAP's of one or multiple controllers ip address. It is used for eg. Omada EAPs, FortiAPs, Zyxel APs, Miktorik APs etc.

Additional information

I've create some code based on how the unifi controller was implemented, but at a higher menu level due to it bieng a generic RFC standard. I've also researched and KEA supports this option natively.