When a new local route is added, an IPIP entry is looked up to determine
whether the route should be offloaded as a tunnel decap or as a trap.
That decision should take into account whether the tunnel netdevice in
question is actually IFF_UP, and only install a decap offload if it is.

Fixes: 0063587d ("mlxsw: spectrum: Support decap-only IP-in-IP tunnels")
Signed-off-by: NPetr Machata <petrm@mellanox.com>
Reviewed-by: NIdo Schimmel <idosch@mellanox.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>