[llvm-branch-commits] [clang] 🍒[NFC][BoundsSafety] Give `counted_by_or_null`, `sized_by`, and `sized_by_or_null` their own documentation (#212877) (PR #217720)

[Douglas Yung via llvm-branch-commits]

dyung wrote:

I was unable to update the source branch, so when I merged in the change to the release branch, it did not auto-resolve this PR.

For reference, this was merged into the release branch in 4e7f3f4e073d16dece9a78bb53ff0dace142d1ac.

https://github.com/llvm/llvm-project/pull/217720