RDMA/mana_ib: register RDMA device with GDMA

Software client needs to register with the RDMA management interface on
the SoC to access more features, including querying device capabilities
and RC queue pair.

Signed-off-by: Long Li <longli@microsoft.com>
Link: https://lore.kernel.org/r/1702692255-23640-2-git-send-email-longli@linuxonhyperv.com


Signed-off-by: Leon Romanovsky <leon@kernel.org>