common/mlx5: support ROCE disable through Netlink

common/mlx5: support ROCE disable through Netlink

Add new 4 Netlink commands to support enable/disable ROCE:
        1. mlx5_nl_devlink_family_id_get to get the Devlink family ID of
           Netlink general command.
        2. mlx5_nl_enable_roce_get to get the ROCE current status.
        3. mlx5_nl_driver_reload - to reload the device kernel driver.
        4. mlx5_nl_enable_roce_set - to set the ROCE status.

When the user changes the ROCE status, the IB device may disappear and
appear again, so DPDK driver should wait for it and to restart itself.

Signed-off-by: Matan Azrad <matan@mellanox.com>
Acked-by: Viacheslav Ovsiienko <viacheslavo@mellanox.com>