common/mlx5: share Netlink commands

common/mlx5: share Netlink commands

Move Netlink mechanism and its dependencies from net/mlx5 to
common/mlx5 in order to be ready to use by other mlx5 drivers.

The dependencies are BITFIELD defines, the ppc64 compilation workaround
for bool type and the function mlx5_translate_port_name.

Update build mechanism accordingly.

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