Enable XZ_DEC_ARM64. am: ae88ba8d2a

Original change: https://android-review.googlesource.com/c/platform/external/xz-embedded/+/2982751

Change-Id: Ic563fb1cb2a88ffe3e3b64b05355b4522abaa0df
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>