mwan3: 23.05 and ipset functionality broken

Maintainer: @feckert
Environment: OpenWrt 23.05

Description:

With the release of 23.05, a critical change to the dnsmasq-full compile options was made where ipset support was removed. This has had a major impact to the mwan3 package and its ipset functionality, given mwan3 does not currently support nfset and now ipset chains will no longer work on 23.05 regardless of any compatibility/translation packages.

Further discussion: https://forum.openwrt.org/t/23-05-dnsmasq-ipsets-and-mwan3-incompatibility/174926

As an initial/short term action, I'll look at updating the documentation to make this clear, I'd imagine various users of mwan3 will be leveraging the ipset functionality.

This however does highlight the need for mwan3 to look at transitioning to nftables without compatibility layers. I appreciate however this is easier said than done, given the complexity and iptables specific code contained within.

Start with the issue description and the linked forum discussion to understand the dnsmasq-full, ipset, and mwan3 compatibility problem. No repository file, test, or entry point is identified, and completion would require defining either the documentation update or a broader nftables transition.