Previously, the address was taken from the state file, but DHCP4_ADDRESS=
entry was dropped by 46986251d6.
Moreover, the link state file is always removed when networkd is
stopping. Let's take the address from the list of enumerated addresses.
https://tools.ietf.org/html/draft-knodel-terminology-02https://lwn.net/Articles/823224/
This gets rid of most but not occasions of these loaded terms:
1. scsi_id and friends are something that is supposed to be removed from
our tree (see #7594)
2. The test suite defines an API used by the ubuntu CI. We can remove
this too later, but this needs to be done in sync with the ubuntu CI.
3. In some cases the terms are part of APIs we call or where we expose
concepts the kernel names the way it names them. (In particular all
remaining uses of the word "slave" in our codebase are like this,
it's used by the POSIX PTY layer, by the network subsystem, the mount
API and the block device subsystem). Getting rid of the term in these
contexts would mean doing some major fixes of the kernel ABI first.
Regarding the replacements: when whitelist/blacklist is used as noun we
replace with with allow list/deny list, and when used as verb with
allow-list/deny-list.
The name with plural made more sense where multiple options could be specified
in one line. After changes in the pull request, this option only accepts one
value, so from users' POV it should be singular.
(The field in the data structure remains plural, because it actually stores
multiple values.)