[clang] [clang] Fix false positive -Wmissing-field-initializer for anonymous unions (PR #70829)

[Henrik G. Olsson via cfe-commits]

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@@ -2537,19 +2555,13 @@ class FieldInitializerValidatorCCC final : public CorrectionCandidateCallback {
 /// actually be initialized.
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hnrklssn wrote:

The comment above looks like it needs to be updated with `@param`s for `FinishSubobjectInit`, `TopLevelObject` and `InitializedFields`.

https://github.com/llvm/llvm-project/pull/70829