[llvm] [NFC][LLVM] Fix some `llvm` namespace usage in Bitcode writer (PR #141709)

[Teresa Johnson via llvm-commits]

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@@ -23,6 +23,7 @@
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/ADT/StringMap.h"
 #include "llvm/ADT/StringRef.h"
+#include "llvm/Analysis/ModuleSummaryAnalysis.h"
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teresajohnson wrote:

I'm not sure including an additional header is superior to just including the extern here below - why make this change?

https://github.com/llvm/llvm-project/pull/141709