net/mlx5e: fix memory leak in mlx5e_ptp_open

When kvzalloc_node or kvzalloc failed in mlx5e_ptp_open, the memory
pointed by "c" or "cparams" is not freed, which can lead to a memory
leak. Fix by freeing the array in the error path.

Fixes: 145e5637 ("net/mlx5e: Add TX PTP port object support")
Signed-off-by: Zhengchao Shao <shaozhengchao@huawei.com>
Reviewed-by: Rahul Rameshbabu <rrameshbabu@nvidia.com>
Reviewed-by: Gal Pressman <gal@nvidia.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

drivers/net/ethernet/mellanox/mlx5/core/en/ptp.c

@@ -729,8 +729,10 @@ int mlx5e_ptp_open(struct mlx5e_priv *priv, struct mlx5e_params *params,
 
 	c = kvzalloc_node(sizeof(*c), GFP_KERNEL, dev_to_node(mlx5_core_dma_dev(mdev)));
 	cparams = kvzalloc(sizeof(*cparams), GFP_KERNEL);
-	if (!c || !cparams)
-		return -ENOMEM;
+	if (!c || !cparams) {
+		err = -ENOMEM;
+		goto err_free;
+	}
 
 	c->priv     = priv;
 	c->mdev     = priv->mdev;