rtnetlink: add new value for DHCP added routes

To improve manageability, it would be good to be able to disambiguate routes
added by administrator from those added by DHCP client.  The only necessary
kernel change is to add value to rtnetlink include file so iproute2 utility
can use it.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/rtnetlink.h b/include/linux/rtnetlink.h
index 35a07c8..ba3254e 100644
--- a/include/linux/rtnetlink.h
+++ b/include/linux/rtnetlink.h
@@ -217,6 +217,7 @@
 #define RTPROT_DNROUTED	13	/* DECnet routing daemon */
 #define RTPROT_XORP	14	/* XORP */
 #define RTPROT_NTK	15	/* Netsukuku */
+#define RTPROT_DHCP	16      /* DHCP client */
 
 /* rtm_scope