net/mlx5e: Implement PSP operations .assoc_add and .assoc_del

Implement .assoc_add and .assoc_del PSP operations used in the tx control
path. Allocate the relevant hardware resources when a new key is registered
using .assoc_add. Destroy the key when .assoc_del is called. Use a atomic
counter to keep track of the current number of keys being used by the
device.

Signed-off-by: Raed Salem <raeds@nvidia.com>
Signed-off-by: Rahul Rameshbabu <rrameshbabu@nvidia.com>
Signed-off-by: Cosmin Ratiu <cratiu@nvidia.com>
Signed-off-by: Daniel Zahka <daniel.zahka@gmail.com>
Link: https://patch.msgid.link/20250917000954.859376-13-daniel.zahka@gmail.com


Signed-off-by: Paolo Abeni <pabeni@redhat.com>