Add file name and line number to libsnapshot logs am: 7f0429fba5 am: a2a51e586a

Original change: https://android-review.googlesource.com/c/platform/system/update_engine/+/2523500

Change-Id: I618ceabc1c01b848d085a8657c92fd48e9c82b2c
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>