When creating a flow rule without the port_id pattern item, always the
PF was selected.
This commit fixes this issue, if no port_id pattern item is available
then we use the port that the flow was created on as source port.
Fixes: 822fb3195348 ("net/mlx5: add port id item to Direct Verbs")
Signed-off-by: Ori Kam <orika@mellanox.com>
Acked-by: Yongseok Koh <yskoh@mellanox.com>