At present the Python code in U-Boot is somewhat inconsistent, with some
files passing pylint quite cleanly and others not.
Add a way to track progress on this clean-up, by checking that no module
has got any worse as a result of changes.
This can be used with 'make pylint'.
Signed-off-by: Simon Glass <sjg@chromium.org>
[trini: Re-generate pylint.base]