Remove /etc/network/interfaces and networking service from device packages

Removed the various /etc/network/interfaces files around and removed from the post-install scripts to enable the networking service. This is not necessary anymore since there is now NetworkManager.

device-sony-castor-windy doesn't require a version bump since the post-install script was not even packaged.

Also removed a duplicate wpa_supplicant entry in postmarketos-base's post-install script and cleaned up a bit.