cros_generate_test_payloads: Fix some lint errors.

Fix some simple lint errors.

BUG=None
TEST=Ran cros lint on cros_generate_test_payloads.py

Change-Id: Ibb2bcb001a52530450c27a4f790fdd29e5daad9d
Reviewed-on: https://chromium-review.googlesource.com/216576
Reviewed-by: Aviv Keshet <akeshet@chromium.org>
Tested-by: Gabe Black <gabeblack@chromium.org>
Commit-Queue: Gabe Black <gabeblack@chromium.org>
1 file changed