net/mlx5: E-Switch, always set mc_promisc for allmulti vports

Set the mc_promisc flag also in the case of adding new mc address to
existing allmulti vport.

Fixes: a35f71f27a61 ('net/mlx5: E-Switch, Implement promiscuous rx modes vf request handling')
Signed-off-by: Mohamad Haj Yahia <mohamad@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/eswitch.c b/drivers/net/ethernet/mellanox/mlx5/core/eswitch.c
index 9b1855b..aebbd6c 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/eswitch.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/eswitch.c
@@ -651,6 +651,7 @@
 					esw_fdb_set_vport_rule(esw,
 							       mac,
 							       vport_idx);
+			iter_vaddr->mc_promisc = true;
 			break;
 		case MLX5_ACTION_DEL:
 			if (!iter_vaddr)