getEthernetName improvement

[jankkm]

Ethernet device names can be customised which broke some of the functionality. Now this is fixed.

[mrodalgaard]

Hi @jankkm,

Great work with the PR, but I need some comments on what you are matching with sed -n "/Device: $(getEthernetInterface))$/{x;p;d;}; x" | sed -e 's/^([0-9]*) \(.*\)$/\1/') and grep -m 1 -o -e 'en[0-9]\{1,3\}'.

Above needs to be covered by test cases. I can help with that, once we have a good description of what you want to achieve.

Also tests are failing for matching Thunderbolt Ethernet and AX88179A, so the extraction needs to be tweaked a little to match all caes.