cdrom: use list_head for cdrom_device_info list

Use list_head for cdrom_device_info list instead of opencoded
singly list handling.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2 files changed