[llvm] Remove CODEOWNERS file and copy missing paths into new-prs-labeler.yml (PR #66145)

[Mehdi Amini via llvm-commits]

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@@ -183,7 +184,8 @@ mlir:index:
   - mlir/**/Index/**
 
 mlir:llvm:
-  - mlir/**/LLVM/**
+  - mlir/**/LLVM*
+  - mlir/**/LLVM*/**
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joker-eph wrote:

Is there a difference between these two patterns for the labelled?

https://github.com/llvm/llvm-project/pull/66145