[llvm] [clang] Include LLVM_VERSION_SUFFIX in the Clang version string. (PR #74469)

[James Y Knight via cfe-commits]

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@@ -650,6 +652,7 @@ if (CLANG_ENABLE_BOOTSTRAP)
     CLANG_VERSION_MAJOR
     CLANG_VERSION_MINOR
     CLANG_VERSION_PATCHLEVEL
+    CLANG_VERSION_SUFFIX
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jyknight wrote:

This list is of CMake variables which automatically get passed through between stages in a multi-stage build, so it is useful here already, if someone specifies a custom CLANG_VERSION_SUFFIX. See docs in llvm/docs/AdvancedBuilds.rst

https://github.com/llvm/llvm-project/pull/74469