bpf_metadata: remove outdated comment

This commit removes an outdated comment about Ingress IP handling.

Currently, the existence of an Ingress source IP with the right IP
family is validated in the config.

See

```
    const Network::Address::Ip* ingress_ip = selectIPVersion(sip->version(), source_addresses);

    if (!ingress_ip) {
      // IP family of the connection has no configured local ingress source address
      ENVOY_LOG(
          warn,
          "cilium.bpf_metadata (north/south L7 LB): No local Ingress IP source address configured "
          "for the family of {}",
          sip->addressAsString());
      return nullptr;
    }
```

Signed-off-by: Marco Hofstetter <[email protected]>

cilium/bpf_metadata.cc

@@ -444,8 +444,6 @@ Cilium::SocketOptionSharedPtr Config::getMetadata(Network::ConnectionSocket& soc
     pod_ip = ingress_ip_str;
 
     // Original source address is never used for north/south LB
-    // This means that a local host IP is used if no IP is configured to be used instead of it
-    // ('ip' above is null).
     src_address = nullptr;
   } else if (!use_original_source_address_ || (npmap_ != nullptr && npmap_->exists(other_ip))) {
     // Otherwise only use the original source address if permitted and the destination is not