selinux: write xattr related codes.

[Gekko0114]

This is an experimental crate. I'll implement a selinux crate step-by-step.
In this PR, I implemented functions related to xattr.

ref: #2718 #2800

[Gekko0114]

Hi @utam0k, @YJDoc2,
I've created this small PR adding the functions related to xattr. Could you review it?

[utam0k]

I'll visit this PR in a couple of days. Please give me some time.

[Gekko0114]

Hi @utam0k, @YJDoc2,
Thanks for your comments and fixed them. Could you take a look again when you have time?

[codecov-commenter]

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Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 66.29%. Comparing base (46fb4ba) to head (3123107).
Report is 17 commits behind head on main.

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Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2825      +/-   ##
==========================================
+ Coverage   66.27%   66.29%   +0.02%     
==========================================
  Files         131      131              
  Lines       16784    16794      +10     
==========================================
+ Hits        11123    11134      +11     
+ Misses       5661     5660       -1     

[YJDoc2]

Hey, a couple of questions, and the CI is failing due to unrelated issues, can you rebase on current main so CI will pass? Thanks!

[YJDoc2]

⚠️ Please install the 'codecov app svg image' to ensure uploads and comments are reliably processed by Codecov.

@utam0k should we remove the codecov bot for now? We are not enforcing the coverage value in CI, and also not maintaining a required threshold for it.

[utam0k]

@utam0k should we remove the codecov bot for now? We are not enforcing the coverage value in CI, and also not maintaining a required threshold for it.

+1 for now. But we'd like to improve our code coverage in the future. It encourages us to add the unit tests.

[Gekko0114]

Hi @utam0k, @YJDoc2
Thanks for your review comments and I've fixed it. Could you take a look again when you have time?

[utam0k]

Awesome!