Revert "Revert^2 "Add the 'bdev_type' attribute to all block devices"" am: f6af322852 am: db5b3355b3 am: ea7557b5b2

Original change: https://android-review.googlesource.com/c/device/linaro/poplar/+/1862419

Change-Id: Idb044756aceb736b2b694bb3954a38f6f515551b