Fix non-deterministic errors with LOCAL_*_x86_64

LOCAL_*_x86_64 was sometimes recognized as a _64 suffix and other times
as the correct _x86_64 suffix, based on the random order of the
propertyPrefixes map.  Replace the map with a slice so that the ordering
is consistent, and ensure 64 as after x86_64.

Change-Id: I1a4b4959f8ef4273ad4a1cdd0672ad557bf1891e
2 files changed