ipv6: export IP6_RT_PRIO_* to userland

The kernel uses some default metric when routes are managed. For example, a
static route added with a metric set to 0 is inserted in the kernel with
metric 1024 (IP6_RT_PRIO_USER).
It is useful for routing daemons to know these values, to be able to set routes
without interfering with what the kernel does.
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/ip6_route.h

 #ifndef _NET_IP6_ROUTE_H
 #define _NET_IP6_ROUTE_H
 
-#define IP6_RT_PRIO_USER	1024
-#define IP6_RT_PRIO_ADDRCONF	256
-
 struct route_info {
 	__u8			type;
 	__u8			length;

include/uapi/linux/ipv6_route.h

@@ -55,4 +55,7 @@ struct in6_rtmsg {
 #define RTMSG_NEWROUTE		0x21
 #define RTMSG_DELROUTE		0x22
 
+#define IP6_RT_PRIO_USER	1024
+#define IP6_RT_PRIO_ADDRCONF	256
+
 #endif /* _UAPI_LINUX_IPV6_ROUTE_H */