net/mlx5e: Update max_opened_tc also when channels are closed

max_opened_tc is used for stats, so that potentially non-zero stats
won't disappear when num_tc decreases. However, mlx5e_setup_tc_mqprio
fails to update it in the flow where channels are closed.

This commit fixes it. The new value of priv->channels.params.num_tc is
always checked on exit. In case of errors it will just be the old value,
and in case of success it will be the updated value.

Fixes: 05909bab ("net/mlx5e: Avoid reset netdev stats on configuration changes")
Signed-off-by: Maxim Mikityanskiy <maximmi@mellanox.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

drivers/net/ethernet/mellanox/mlx5/core/en_main.c

@@ -3627,12 +3627,10 @@ static int mlx5e_setup_tc_mqprio(struct mlx5e_priv *priv,
 
 	err = mlx5e_safe_switch_channels(priv, &new_channels,
 					 mlx5e_num_channels_changed_ctx, NULL);
-	if (err)
-		goto out;
 
-	priv->max_opened_tc = max_t(u8, priv->max_opened_tc,
-				    new_channels.params.num_tc);
 out:
+	priv->max_opened_tc = max_t(u8, priv->max_opened_tc,
+				    priv->channels.params.num_tc);
 	mutex_unlock(&priv->state_lock);
 	return err;
 }