exclude NetworkInterface where not supported

Exclude NetworkInterface and MulticastSocket on platforms where we do
not have network interface detection implemented

Net/testsuite/src/MulticastSocketTest.h

@@ -37,6 +37,11 @@
 
 
 #include "Poco/Net/Net.h"
+
+
+#ifdef POCO_NET_HAS_INTERFACE
+
+
 #include "CppUnit/TestCase.h"
 
 
@@ -57,4 +62,7 @@ private:
 };
 
 
+#endif // POCO_NET_HAS_INTERFACE
+
+
 #endif // MulticastSocketTest_INCLUDED