net/mlx5e: Expose the VF/SF RX drop counter on the representor

net/mlx5e: Expose the VF/SF RX drop counter on the representor

Q counters are device-level counters that track specific
events, among which are out_of_buffer events. These events
occur when packets are dropped due to a lack of receive
buffer in the RX queue.

Expose the total number of out_of_buffer events on the
VFs/SFs to their respective representor, using the
"ip stats group link" under the name of "rx_missed".

The "rx_missed" equals the sum of all
Q counters out_of_buffer values allocated on the VFs/SFs.

Signed-off-by: Carolina Jubran <cjubran@nvidia.com>
Reviewed-by: Gal Pressman <gal@nvidia.com>
Reviewed-by: Aya Levin <ayal@nvidia.com>
Reviewed-by: Rahul Rameshbabu <rrameshbabu@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Link: https://lore.kernel.org/r/20240410214154.250583-1-tariqt@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>