[PATCH 02/14] drbd: remove dead code in device_to_statistics

[Johannes Thumshirn]

On 22/07/2020 08:28, Christoph Hellwig wrote:
> Ever since the switch to blk-mq, a lower device not use by VM
                                           in-use/used? ~^

Also this looks like the last user of 'dev_lower_blocked' so it could
be removed from device_statistics if it's not an ABI (not sure with this
netlink stuff).