network-interfaces-scripted: don't add 'lo' as device dependency

systemd does not create device units for loopback devices,
since they are not physical.

nixos/modules/tasks/network-interfaces-scripted.nix

@@ -71,7 +71,7 @@ let
              (hasAttr dev cfg.vswitches) ||
              (hasAttr dev cfg.wlanInterfaces)
           then [ "${dev}-netdev.service" ]
-          else optional (dev != null && !config.boot.isContainer) (subsystemDevice dev);
+          else optional (dev != null && dev != "lo" && !config.boot.isContainer) (subsystemDevice dev);
 
         networkLocalCommands = {
           after = [ "network-setup.service" ];