[clang] [Clang][Diagnostics] Update select uses in DiagnosticXKinds.td to use enum_select (PR #130868)

[Erich Keane via cfe-commits]

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@@ -71,721 +71,704 @@
 
 using namespace clang;
 using llvm::APFixedPoint;
+using llvm::APFloat;
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erichkeane wrote:

DEFINITELY looks like you clang-formatted this entire file.  Please don't!  I can't see what the changes you made here were.

https://github.com/llvm/llvm-project/pull/130868