net/mlx5: update install/uninstall event handlers

net/mlx5: update install/uninstall event handlers

We are implementing the support for multiport Infiniband device
with representors attached to these multiple ports. Asynchronous
device event notifications (link status change, removal event, etc.)
should be shared between ports. We are going to implement shared
event handler and this patch introduces appropriate device
structure changes and updated event handler install and uninstall
routines.

Signed-off-by: Viacheslav Ovsiienko <viacheslavo@mellanox.com>
Acked-by: Shahaf Shuler <shahafs@mellanox.com>