IB/mlx5: Implement the ODP capability query verb

The patch adds infrastructure to query ODP capabilities in the mlx5
driver. The code will read the capabilities from the device, and
enable only those capabilities that both the driver and the device
supports.  At this point ODP is not supported, so no capability is
copied from the device, but the patch exposes the global ODP device
capability bit.

Signed-off-by: Shachar Raindel <raindel@mellanox.com>
Signed-off-by: Haggai Eran <haggaie@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>