tests/functional: tell pylint not to check c-modules

To fix: qemu-test.test_pylint "/home/alex/lsrc/qemu.git/tests/functional/arm/test_integratorcp.py:83: I1101: Module 'cv2' has no 'imread' member, but source is unavailable. Consider adding this module to extension-pkg-allow-list if you want to perform analysis based on run-time introspection of living objects. (c-extension-no-member)" Manually running python3 showed I could indeed import cv2 and call those functions. Rather than allowing pylint to introspect lets just tell it to skip c modules. Reviewed-by: Daniel P. Berrangé <berrange@redhat.com> Reviewed-by: Thomas Huth <thuth@redhat.com> Message-ID: <20260619155657.944220-5-alex.bennee@linaro.org> Signed-off-by: Alex Bennée <alex.bennee@linaro.org>