Feature Request -- Add dhcp and farp plugins to strongswan.

[fatrogue1]

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• I have read the contributing guide lines at https://github.com/opnsense/plugins/blob/master/CONTRIBUTING.md
• I have searched the existing issues, open and closed, and I'm convinced that mine is new.

Is your feature request related to a problem? Please describe.
I use the native Windows VPN clients when connecting to the VPN over IKEv2. If i want split routing without configuring manually anything, i need to forward the DHCP request to the DHCP-server: windows VPN client sends a DHCP request upon connection and adds routes supplied in option 249 of the DHCP reply.

Describe the solution you'd like
This can only be achieved with the strongswan's dhcp plugin. DHCP plugin is now succesfully ported to FreeBSDs Strongswan and available in the version 5.9.14 https://github.com/strongswan/strongswan/releases/tag/5.9.14

Describe alternatives you've considered
Unfortunately, there are no other alternatives to solve this problem.