net/mlx5e: Dynamically allocate DIM structure for SQs/RQs

Make it possible for the DIM structure to be torn down while an SQ or RQ is
still active. Changing the CQ period mode is an example where the previous
sampling done with the DIM structure would need to be invalidated.

Co-developed-by: Nabil S. Alramli <dev@nalramli.com>
Signed-off-by: Nabil S. Alramli <dev@nalramli.com>
Co-developed-by: Joe Damato <jdamato@fastly.com>
Signed-off-by: Joe Damato <jdamato@fastly.com>
Signed-off-by: Rahul Rameshbabu <rrameshbabu@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Link: https://lore.kernel.org/r/20240419080445.417574-4-tariqt@nvidia.com


Signed-off-by: Jakub Kicinski <kuba@kernel.org>