[GitHub] Add main LLVM Dialect path to MLIR LLVM PR subscribers (#65513)

The LLVM Dialect in MLIR, which the `mlir-llvm` team is supposed to
provide notifications for, is 98% not nested in a directory called LLVM
but rather LLVMIR. The former only contains some tests.

This should make PRs such as
#65508 add the team as
codeowner.

Author: zero9178

.github/CODEOWNERS

@@ -119,7 +119,7 @@
 /mlir/**/Index/ @llvm/pr-subscribers-mlir-index
 
 # mlir-llvm
-/mlir/**/LLVM/ @llvm/pr-subscribers-mlir-llvm
+/mlir/**/LLVM* @llvm/pr-subscribers-mlir-llvm
 
 # mlir-linalg
 /mlir/**/*Linalg @llvm/pr-subscribers-mlir-linalg