[clang] [clang][NFC] Annotate `Type` bit-fields with `clang::preferred_type` (PR #70349)

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@@ -20,7 +20,7 @@ namespace clang {
 
 /// Describes the different kinds of linkage
 /// (C++ [basic.link], C99 6.2.2) that an entity may have.
-enum Linkage : unsigned char {
+enum Linkage : unsigned {
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cor3ntin wrote:

can you explain this change?

https://github.com/llvm/llvm-project/pull/70349