ota_extractor: improve logging am: ee293badde am: 3d17336a01

Original change: https://android-review.googlesource.com/c/platform/system/update_engine/+/3164520

Change-Id: Id045549de003ebfc87f900d291f224e36f9b74de
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>