RDMA/core: Unify style of IOCTL commands

MAD and HFI1 have different naming convention, this patch
simplifies and unifies their defines and names.

As part of cleanup, the HFI1 _NUM() macro and command indexes
were removed (controversial). This will cause intentional (and
arguably unnecessary) breakage to the PSM user space library.

Signed-off-by: Matan Barak <matanb@mellanox.com>
Signed-off-by: Haggai Eran <haggaie@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Reviewed-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>