Add aarch64-linux-musl configurations for cpython2 am: f78b0c41fd am: f956773443 am: 6f11761619

Original change: https://android-review.googlesource.com/c/platform/external/python/cpython2/+/2159996

Change-Id: I7028a0b13c8ab16b9d3a6653320b23d4e966e0b1
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>