[llvm] Add myself to CODEOWNERS (PR #66363)

[Alex Bradbury via llvm-commits]

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@@ -1,4 +1,27 @@
+# This file lists reviewers that are auto-assigned when a pull request modifies
+# certain files or directories. If you add yourself to this file, you commit to
+# reviewing a large fraction of pull requests in the relevant area.
+#
+# The GitHub "code owners" mechanism is used exclusively to auto-assign
+# reviewers and does not carry significance beyond that. It is not necessary
+# to receive an approval from a "code owner" in particular -- any LLVM project
+# member can approve pull requests.
+#
+# Note that GitHub's concept of "code owner" is independent from LLVM's own
+# "code owner" concept, they merely happen to share terminology. See the
+# CODE_OWNERS.txt files in the respective subproject directories.
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asb wrote:

I'd additionally link to https://llvm.org/docs/DeveloperPolicy.html#code-owners

https://github.com/llvm/llvm-project/pull/66363