kernel: net/mlx5e: Use a memory barrier to enforce PTP WQ xmit submission tracking occurs after populating the metadata_map

A vulnerability was found in the mlx5etxwqecomplete function in the Linux kernel. The CPU or compiler may reorder two of the functions: mlx5eptpmetadatamapput and mlx5eptpsqtrackmetadata, and a situation could arise where metadata tracking occurs before the metadata map is fully populated. This...