python: Stabilize some script outputs

python: Stabilize some script outputs

In Python, dictionaries and sets are unordered, and as a result their
is no guarantee that running this script twice will produce the same
output.

Using ordered dicts and explicitly sorting items makes the build more
reproducible, and will make it possible to verify that we're not
breaking anything when we move the build scripts to Python 3.

Reviewed-by: Eric Engestrom <eric.engestrom@intel.com>