Lighthouse logs "UPnP route established" when UPnP is disabled

## Description

I'm running Lighthouse beacon node with `--disable-upnp` and notice the following logs:

```
Mar 20 05:04:49.563 INFO UPnP route established                  addr: /ip4/xxx.xxx.xxx.xxx/udp/9501/quic-v1, service: libp2p
```

This is a bug as it shouldn't happen when UPnP is disabled.

## Version

`stable` (v5.1.0)
