ipv4: fib: Set offload indication according to nexthop flags

We're going to have capable drivers indicate route offload using the
nexthop flags, but for non-multipath routes these flags aren't dumped to
user space.

Instead, set the offload indication in the route message flags.
Signed-off-by: NIdo Schimmel <idosch@mellanox.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Acked-by: NDavid Ahern <dsahern@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/ipv4/fib_semantics.c

@@ -1342,6 +1342,8 @@ int fib_dump_info(struct sk_buff *skb, u32 portid, u32 seq, int event,
 			    IN_DEV_IGNORE_ROUTES_WITH_LINKDOWN(in_dev))
 				rtm->rtm_flags |= RTNH_F_DEAD;
 		}
+		if (fi->fib_nh->nh_flags & RTNH_F_OFFLOAD)
+			rtm->rtm_flags |= RTNH_F_OFFLOAD;
 #ifdef CONFIG_IP_ROUTE_CLASSID
 		if (fi->fib_nh[0].nh_tclassid &&
 		    nla_put_u32(skb, RTA_FLOW, fi->fib_nh[0].nh_tclassid))