servo: remove networking.useDHCP=false override

seems likely that the change to systemd-networkd renamed the ethernet interface, and so eth0.useDHCP wasn't right. this change seems to restore networking

hosts/by-name/servo/net.nix

@@ -24,12 +24,6 @@ in
     sane.ports.openFirewall = true;
     sane.ports.openUpnp = true;
 
-    # these useDHCP lines are legacy from the auto-generated config. might be safe to remove now?
-    networking.useDHCP = false;
-    networking.interfaces.eth0.useDHCP = true;
-    # XXX colin: probably don't need this. wlan0 won't be populated unless i touch a value in networking.interfaces.wlan0
-    networking.wireless.enable = false;
-
     # this is needed to forward packets from the VPN to the host
     boot.kernel.sysctl."net.ipv4.ip_forward" = 1;
 

hosts/modules/wg-home.nix

@@ -110,6 +110,7 @@ in
       }
       (lib.mkIf cfg.forwardToWan {
         # documented here: <https://nixos.wiki/wiki/WireGuard#Server_setup_2>
+        # TODO: don't hardcode eth0!
         postSetup = ''
           ${pkgs.iptables}/bin/iptables -t nat -A POSTROUTING -s ${cfg.ip}/24 -o eth0 -j MASQUERADE
         '';