I think the name 'listenAddress' is more descriptive. Other NixOS
modules that define 'host' either use it as listen address or as address
a client connects to. listenAddress is unambiguous.
The addition of 'host' was added earlier today[1], so not bothering with
./nixos/modules/rename.nix.
[1]: 44ea184997 ("jenkins ci enhancement: add port and prefix option")