Use lowercase machine architecture.
Use lowercase machine architecture.

Bug: 896355
Change-Id: I83a3c27478029d90206b5bb26e26797df47a90f6
Reviewed-on: https://chromium-review.googlesource.com/c/1287244
Reviewed-by: Andrii Shyshkalov <a30c74fa30536fe7ea81ed6dec202e35e149e1fd@chromium.org>
Commit-Queue: Edward Lesmes <d05609f027dc667cc37492b1dc1bdea5d60fa82a@chromium.org>

CoherentLabs/depot_tools,CoherentLabs/depot_tools