Cannot use static IP addresses with new EthernetInterface API

[janjongboom]

There's no way to set a static IP address in EthernetInterface in mbed OS 5 anymore. When is that coming back?

[geky]

There is a patch currently in the works (branch), but we are taking care to introduce an implementation that will be forward compatible with the network-socket API to avoid code changes as much as possible.

Sorry for the inconvenience.

[janjongboom]

@geky OK, great.

[ciarmcom]

ARM Internal Ref: IOTMORF-484

[geky]

Related pr: #2664