nixos/mosquitto: Migrate away from bind_address/port config keys

Fixes these two deprecation warnings, by moving away from these options
towards a simple listener configuration.

> The 'bind_address' option is now deprecated and will be removed in a future version. The behaviour will default to true.
> The 'port' option is now deprecated and will be removed in a future version. Please use 'listener' instead.

Fixes: #120860

nixos/modules/services/networking/mosquitto.nix

@@ -20,8 +20,7 @@ let
     acl_file ${aclFile}
     persistence true
     allow_anonymous ${boolToString cfg.allowAnonymous}
-    bind_address ${cfg.host}
-    port ${toString cfg.port}
+    listener ${toString cfg.port} ${cfg.host}
     ${passwordConf}
     ${listenerConf}
     ${cfg.extraConf}