[clang] [clang][NFC] Refactor Builtins.def to be a tablegen file (PR #68324)

[Timm Baeder via cfe-commits]

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@@ -172,6 +173,8 @@ cl::opt<ActionType> Action(
                    "Generate clang attribute text node dumper"),
         clEnumValN(GenClangAttrNodeTraverse, "gen-clang-attr-node-traverse",
                    "Generate clang attribute traverser"),
+        clEnumValN(GenClangBuiltins, "gen-clang-builtins",
+                   "Generate clanhg builtins list"),
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tbaederr wrote:

```suggestion
                   "Generate clang builtins list"),
```

https://github.com/llvm/llvm-project/pull/68324