Tweaks to clean files scripts and file list

[hyperupcall]

Description

I noticed that all files under lib/* were manually specified in clean_files.txt. I refactored that to the first section.

When running the lint_clean_files.sh script, I receieve the following message:

xargs: warning: options --max-args and --replace/-I/-i are mutually exclusive, ignoring previous --max-args value
...

Because the previuos --max-args / -n value is ignored anyways, and to remove the warning, I removed that option from the script.

Motivation and Context

This simplifes the cleaning files workflow.

How Has This Been Tested?

By executing ./lint_clean_files.sh. And double-checking to ensure that directories are, in fact, supported by clean_files.txt.

Screenshots (if appropriate):

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• My code follows the code style of this project.
• If my change requires a change to the documentation, I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• If I have added a new file, I also added it to clean_files.txt and formatted it using lint_clean_files.sh.
• I have added tests to cover my changes, and all the new and existing tests pass.