DDS should use the same networking configuration as other IP networking

[timtuxworth]

As per the discussion on this PR #28815, DDS is using a different architecture for IP networking support than the rest of AP. It should be consistent.

This is going to be one of the first things that I and others will want to do when using ROS2/DDS will be to connect the AP to an ethernet switch, either using the PPP interface or ethernet. ArduPilot will need to communicate with one or more gimbal/cameras, AI module and ROS2/DDS and other services running on a companion computer, using the same physical port on the AP.

This is a lot easier to do if the devices can use their "out of the box" configured 192.168.144.* IP addresses, with the only interface needing to be configured being the ethernet port on the companion computer.

This is why I previously suggested that DDS should not be doing it's own networking - it should use the IP addresses configured in the NET* parameters and should be able to run as a NET_Pn_PROTOCOL, so all these devices can be connected over a single physical port to the AP.

There is a suggestion that there might be performance concerns with this change. I don't see any justification for that, but I'd be surprised if it doesn't save some flash.

Platform
[X] All
[ ] AntennaTracker
[ ] Copter
[ ] Plane
[ ] Rover
[ ] Submarine