Added a field to set enable_vabc am: 9fc62b8132 am: 3420382c05

Original change: https://android-review.googlesource.com/c/platform/system/update_engine/+/2508075

Change-Id: I945011e4d7497c15c2f8d35c5e0c30dcf2482fd5
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>