IPv4 addresses not parsed correctly in IIS

Port number is included when passed to tree_contains_ip(..) and code attempts to parse as an IPv6 address.

Error is raised to Windows Event Log when doing IPmatch rules

```
[client 213.78.82.1:34984] ModSecurity: IPmatch: bad IPv6 specification "213.78.82.1:34984". [hostname "ACTUSAA1"] [uri "/api/ping"] [unique_id "16717361818946771401"]
```
