[clang-tools-extra] [clang] [clang] Refactor `clang::Linkage` (PR #71049)

[Chuanqi Xu via cfe-commits]

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@@ -2214,7 +2214,7 @@ void ASTWriter::WriteDeclAbbrevs() {
   Abv->Add(BitCodeAbbrevOp(0));                       // TSCSpec
   Abv->Add(BitCodeAbbrevOp(0));                       // InitStyle
   Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isARCPseudoStrong
-  Abv->Add(BitCodeAbbrevOp(0));                       // Linkage
+  Abv->Add(BitCodeAbbrevOp(1));                         // Linkage
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ChuanqiXu9 wrote:

```suggestion
  Abv->Add(BitCodeAbbrevOp(1));                         // Linkage::None
```

nit

https://github.com/llvm/llvm-project/pull/71049