Mwan3: nftables porting help

@jow @aaronjg Porting to the new firewall nftables backend is not quite trivial. I have problems with the ipsets.
I am now trying to use the new tool

ipset-translate restore

to use my mwan3 ipsets with nftables.

This tool is included in the new ipset 7.15. This was already added by me and merged in the openwrt master branch https://github.com/openwrt/openwrt/commit/ba6a48366f4ae4b7b47a11f95141554c52a2a5db

I have a problem with the following ipset. There seems to be no translation for it:

Can anyone tell me how to do this?

I would like to rewrite the mwan3 so that it use ucode like the firewall4. Unfortunately, I probably won't be able to do that until the freeze. Also, I would first have to read into ucode and restructure the whole mwan3.

Therefore, my only option is to work with translate.

I would be happy about any help and discussion with some feedback

With the following pullrequest [WIP] I have already started to prepare the mwan3 so that it also works with nftables.