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>