Reduce frequency of sync() in update_engine logging am: d2a298df41 am: e47a2a1810 am: 0c76f4d2d0

Original change: https://android-review.googlesource.com/c/platform/system/update_engine/+/2895963

Change-Id: I9fa1d602aab703f25b186d6b0e9236f17dc83a74
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>