upnp: add compatibility for miniupnpc 2.2.8

See: https://github.com/miniupnp/miniupnp/commit/c0a50ce33e3b99ce8a96fd43049bb5b53ffac62f

The return value of 2 now indicates:
"A valid connected IGD has been found but its IP address is reserved (non routable)"

We continue to ignore any return value other than 1.

src/mapport.cpp

@@ -161,8 +161,11 @@ static bool ProcessUpnp()
     struct UPNPUrls urls;
     struct IGDdatas data;
     int r;
-
+#if MINIUPNPC_API_VERSION <= 17
     r = UPNP_GetValidIGD(devlist, &urls, &data, lanaddr, sizeof(lanaddr));
+#else
+    r = UPNP_GetValidIGD(devlist, &urls, &data, lanaddr, sizeof(lanaddr), nullptr, 0);
+#endif
     if (r == 1)
     {
         if (fDiscover) {