[IPV6] MIP6: Add home address option definition.

Add home address option definition for Mobile IPv6.
Based on MIPL2 kernel patch.
Signed-off-by: Noriaki TAKAMIYA <takamiya@po.ntts.co.jp>
Signed-off-by: Masahide NAKAMURA <nakam@linux-ipv6.org>
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/linux/in6.h

@@ -142,6 +142,7 @@ struct in6_flowlabel_req
 #define IPV6_TLV_PADN		1
 #define IPV6_TLV_ROUTERALERT	5
 #define IPV6_TLV_JUMBO		194
+#define IPV6_TLV_HAO		201	/* home address option */
 
 /*
  *	IPV6 socket options

include/linux/ipv6.h

@@ -86,6 +86,16 @@ struct rt2_hdr {
 #define rt2_type		rt_hdr.type
 };
 
+/*
+ *	home address option in destination options header
+ */
+
+struct ipv6_destopt_hao {
+	__u8			type;
+	__u8			length;
+	struct in6_addr		addr;
+} __attribute__ ((__packed__));
+
 struct ipv6_auth_hdr {
 	__u8  nexthdr;
 	__u8  hdrlen;           /* This one is measured in 32 bit units! */