Upgrade xz-embedded to 3f438e15109229bb14ab45f285f4bff5412a9542 am: 6e6257f536 am: b7e6cc6d06

Original change: https://android-review.googlesource.com/c/platform/external/xz-embedded/+/1853701

Change-Id: I681d7d5fb3faee554fec2910eb5e28ebaa05195c