test/py: Disable error E0611 in two cases for pylint

Recently pylint has started to complain about:
No name 'fs_helper' in module 'tests' (no-name-in-module)

Due to:
from tests import fs_helper

However, we have:
test/py/tests/fs_helper.py

And since we do not want to add a dummy test/py/tests/__init__.py to
silence this warning we instead just disable it as needed.

Cc: Simon Glass <sjg@chromium.org>
Signed-off-by: Tom Rini <trini@konsulko.com>