include: Add PF_INET6 define.

Signed-off-by: Alistair Leslie-Hughes <leslie_alistair@hotmail.com>
Signed-off-by: Alexandre Julliard <julliard@winehq.org>

include/winsock2.h

@@ -92,6 +92,12 @@ extern "C" {
 #define WS_SOCK_SEQPACKET          5
 #endif /* USE_WS_PREFIX */
 
+/* protocol families */
+
+#ifndef USE_WS_PREFIX
+#define PF_INET6                   AF_INET6
+#endif
+
 /* option flags per socket */
 
 #define FD_MAX_EVENTS              10