[automerger skipped] Revert "DO NOT MERGE: Enable mainline prebuilts for...

[automerger skipped] Revert "DO NOT MERGE: Enable mainline prebuilts for device targets" am: e7559159 -s ours

am skip reason: subject contains skip directive

Original change: https://googleplex-android-review.googlesource.com/c/platform/build/+/24669690



Change-Id: I2cd3238760023c98abf38942f094030c9ef33a35
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>