net/mlx5: DR, Warn and ignore SW steering rule insertion on QP err

In the event of SW steering QP entering error state, SW steering
cannot insert more rules, and will silently ignore the insertion
after issuing a warning.

Signed-off-by: Yuval Avnery <yuvalav@mellanox.com>
Signed-off-by: Yevgeny Kliteynik <kliteyn@nvidia.com>
Reviewed-by: Alex Vesker <valex@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>