[DO NOT MERGE] Migrate the blkio controller to the v2 cgroup hierarchy am: eef0f563fd

Original change: https://android-review.googlesource.com/c/platform/system/core/+/2378990

Change-Id: I781865e89ddd58075908f3803d15d4cf0d803111
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>