nexthop: Remove NEXTHOP_EVENT_ADD

Not used anywhere.
Signed-off-by: NIdo Schimmel <idosch@nvidia.com>
Suggested-by: NDavid Ahern <dsahern@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

include/net/nexthop.h

@@ -105,7 +105,6 @@ struct nexthop {
 };
 
 enum nexthop_event_type {
-	NEXTHOP_EVENT_ADD,
 	NEXTHOP_EVENT_DEL
 };