Bug#960897: [Android-tools-devel] Bug#960897: Update android-platform-external-libunwind and build for ppc64el

[Hans-Christoph Steiner]

We are not keeping up with the maintenance on the Google supported
archs.  Adding archs that are explicitly not supported by upstream will
complicate things further.  To support other archs, someone will need to
contribute both to the ongoing maintenance on the supported arches, as
well as the patches to enable other archs.