previous commit broke update checker, fix it

plugins/upd/upd.c

@@ -70,7 +70,7 @@ print_version ()
 {
 	char *version = check_version ();
 
-	if (strcmp (version, xchat_get_info (ph, "version")) == 0)
+	if (strcmp (version, xchat_get_info (ph, "wdk_version")) == 0)
 	{
 		xchat_printf (ph, "You have the latest version of XChat-WDK installed!\n");
 	}