Allow cipd to interpret UNAME aarch64 as arm64 architecture
Allow cipd to interpret UNAME aarch64 as arm64 architecture

BUG=768318
R=phajdan.jr@chromium.org
R=8400006a9338a0893dca0101ad49838955bd6b2c@chromium.org
R=40f3d43a28ebae3cb819288542e1c84d73d962d5@chromium.org

Change-Id: I2c85f9d30e74cfaebf2718bee075d6a21a6e0421
Reviewed-on: https://chromium-review.googlesource.com/708738
Reviewed-by: Daniel Jacques <8400006a9338a0893dca0101ad49838955bd6b2c@chromium.org>
Reviewed-by: Robbie Iannucci <40f3d43a28ebae3cb819288542e1c84d73d962d5@chromium.org>
Commit-Queue: William Hesse <a821cddceae7dc400f272e3cb1a72f400f9fed6d@google.com>

CoherentLabs/depot_tools,CoherentLabs/depot_tools