NET_IPV6_ROUTE_FLUSH
NET_IPV6_ROUTE_GC_THRESH
NET_IPV6_ROUTE_MAX_SIZE
NET_IPV6_ROUTE_GC_MIN_INTERVAL
NET_IPV6_ROUTE_GC_TIMEOUT
NET_IPV6_ROUTE_GC_INTERVAL
NET_IPV6_ROUTE_GC_ELASTICITY
NET_IPV6_ROUTE_MTU_EXPIRES
NET_IPV6_ROUTE_MIN_ADVMSS
NET_IPV6_ROUTE_GC_MIN_INTERVAL_MS