IB/mlx5: Add DEVX support for modify and query commands

Add support in DEVX for modify and query commands, the required lock is
taken (i.e. READ/WRITE) by the KABI infrastructure accordingly.

Signed-off-by: Yishai Hadas <yishaih@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>