net/mlx5: Register mlx5e priv to devcom in MPV mode

If the device is in MPV mode, the ethernet driver would now register
to events from IB driver about core devices affiliation or
de-affiliation.

Use the key provided in said event to connect each mlx5e priv
instance to it's master counterpart, this way the ethernet driver
is now aware of who is his master core device and even more, such
as knowing if partner device has IPsec configured or not.

Signed-off-by: Patrisious Haddad <phaddad@nvidia.com>
Reviewed-by: Mark Bloch <mbloch@nvidia.com>
Link: https://lore.kernel.org/r/279adfa0aa3a1957a339086f2c1739a50b8e4b68.1695296682.git.leon@kernel.org


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