[PATCH v4] nvme: Skip trace complete_rq on host path error

[hch at lst.de]

> -	trace_nvme_complete_rq(req);
> +	if (nvme_req(req)->status != NVME_SC_HOST_PATH_ERROR)
> +		trace_nvme_complete_rq(req);
> +

Please add a comment here explaining why we need the check.