Merge "libprefetch: Start prefetch service based on build" into main am: 3ffdc620 am: 36252ab7

Original change: https://android-review.googlesource.com/c/platform/system/core/+/3368783



Change-Id: I91d8cfc9ee0a073d547e2faeedd1b835d320abf7
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>