#2 Windows 2000 support

[Jaap Keuter]

This change allows GeoIP 1.4.6 to work with Windows 2000.
ref: https://bugs.wireshark.org/bugzilla/show_bug.cgi?id=4176#c12
ref: http://msdn.microsoft.com/en-us/library/ms737931\(VS.85).aspx

GeoIP-1.4.6-win32ws\libGeoIP\GeoIP.h
@@ -34,6 +34,7 @@
#else /* !defined(_WIN32) */
#include <winsock2.h>
#include <ws2tcpip.h>
+#include <wspiapi.h>
#include <windows.h>
#define snprintf _snprintf