common/mlx5: fix device list operations concurrency

common/mlx5: fix device list operations concurrency

The mlx5 common driver has a global list of mlx5 devices which are
probed.

In probe function it creates one and insert it to the list. Similarly it
removes the device in remove function.
These operations are not safe as there can be such operations in
parallel, by different threads.

Add global lock for the list and use it to insert or remove.

Fixes: 8a41f4deccc3 ("common/mlx5: introduce layer for multiple class drivers")
Cc: stable@dpdk.org
Signed-off-by: Michael Baum <michaelba@nvidia.com>
Acked-by: Matan Azrad <matan@nvidia.com>