net/mlx5e: Expose catastrophic steering error counters

Add generated_pkt_steering_fail and handled_pkt_steering_fail to devlink
heatlth reporter.
generated_pkt_steering_fail indicates the number of packets dropped due to
illegal steering operation within the vport steering domain.
handled_pkt_steering_fail indicates the number of packets dropped due to
illegal steering operation, originated by the vport.

Also, update devlink reporter functionality documentation with the newly
exposed counters.

Signed-off-by: Lama Kayal <lkayal@nvidia.com>
Reviewed-by: Rahul Rameshbabu <rrameshbabu@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>