core: frontend: Add option to disable network interface

### Current behaviour

It's not possible to remove dynamic ips since it's configured by the modem.
It's right now not possible to not use a network interface that has a modem.

### Expected or desired behaviour

It would help to have an option to disable/enable network interfaces, maintaining configuration, but the device would be disable for the OS.

### Prerequisites

- [X] I have checked to make sure that a similar request has not already been filed or fixed.