The flow counters binding support commit introduced a code change where
none NULL 'rule_dest' is always passed to mlx5_add_flow_rules, this breaks
'DON'T_TRAP' rules insertion.
The fix uses the equivalent 'dest_num' value instead of dest pointer
at the failed check.
fixes: 
3b3233fbf02e ('IB/mlx5: Add flow counters binding support')
Signed-off-by: Raed Salem <raeds@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
        if (flow_act->action == MLX5_FLOW_CONTEXT_ACTION_FWD_NEXT_PRIO) {
                if (!fwd_next_prio_supported(ft))
                        return ERR_PTR(-EOPNOTSUPP);
-               if (dest)
+               if (dest_num)
                        return ERR_PTR(-EINVAL);
                mutex_lock(&root->chain_lock);
                next_ft = find_next_chained_ft(prio);