only determine default port if it is in a public addr

p2p/host/relay/autorelay.go

@@ -291,6 +291,10 @@ func cleanupAddressSet(pi pstore.PeerInfo) pstore.PeerInfo {
 	// pass-1: find default port
 	has4001 := false
 	for _, addr := range pi.Addrs {
+		if manet.IsPrivateAddr(addr) {
+			continue
+		}
+
 		port, err := tcpPort(addr)
 		if err != nil {
 			continue