net: Add link-local addressing support

Code based on networking/zcip.c in busybox
commit 8531d76a15890c2c535908ce888b2e2aed35b172

Signed-off-by: Joe Hershberger <joe.hershberger@ni.com>

net/link_local.h

@@ -0,0 +1,24 @@
+/*
+ * RFC3927 ZeroConf IPv4 Link-Local addressing
+ * (see <http://www.zeroconf.org/>)
+ *
+ * Copied from BusyBox - networking/zcip.c
+ *
+ * Copyright (C) 2003 by Arthur van Hoff (avh@strangeberry.com)
+ * Copyright (C) 2004 by David Brownell
+ *
+ * Licensed under the GPL v2 or later
+ */
+
+#if defined(CONFIG_CMD_LINK_LOCAL)
+
+#ifndef __LINK_LOCAL_H__
+#define __LINK_LOCAL_H__
+
+#include <common.h>
+
+void link_local_receive_arp(struct arp_hdr *arp, int len);
+void link_local_start(void);
+
+#endif /* __LINK_LOCAL_H__ */
+#endif