[lld] [lld][COFF]Expose UnifiedLTO options (PR #69904)

[via llvm-commits]

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@@ -17,6 +17,7 @@
 #include "llvm/Object/COFF.h"
 #include "llvm/Support/CachePruning.h"
 #include "llvm/Support/VirtualFileSystem.h"
+#include "llvm/LTO/LTO.h"
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Naville wrote:

Maybe that's why ELF's implementation redeclared those enums...

https://github.com/llvm/llvm-project/pull/69904