lib/tc: Fix flow dump for tunnel id equal zero

Tunnel id 0 is not printed unless tunnel flag FLOW_TNL_F_KEY is set.
Fix that by always setting FLOW_TNL_F_KEY when tunnel id is valid.

Fixes: 0227bf0 ("lib/tc: Support optional tunnel id")
Signed-off-by: Dmytro Linkin <dmitrolin@mellanox.com>
Reviewed-by: Roi Dayan <roid@mellanox.com>
Signed-off-by: Simon Horman <simon.horman@netronome.com>

lib/netdev-offload-tc.c

@@ -600,6 +600,7 @@ parse_tc_flower_to_match(struct tc_flower *flower,
     if (flower->tunnel) {
         if (flower->mask.tunnel.id) {
             match_set_tun_id(match, flower->key.tunnel.id);
+            match->flow.tunnel.flags |= FLOW_TNL_F_KEY;
         }
         if (flower->key.tunnel.ipv4.ipv4_dst) {
             match_set_tun_src(match, flower->key.tunnel.ipv4.ipv4_src);