dcdbas: use memory_read_from_buffer()

			     struct bin_attribute *bin_attr,

			     char *buf, loff_t pos, size_t count)

{

	size_t max_read;

	ssize_t ret;

	mutex_lock(&smi_data_lock);

	if (pos >= smi_data_buf_size) {

		ret = 0;

		goto out;

	}

	max_read = smi_data_buf_size - pos;

	ret = min(max_read, count);

	memcpy(buf, smi_data_buf + pos, ret);

out:

	ret = memory_read_from_buffer(buf, count, &pos, smi_data_buf,

					smi_data_buf_size);

	mutex_unlock(&smi_data_lock);

	return ret;

}