[llvm] [HLSL] Refactoring DXILABI.h to not depend on scope printer (PR #153840)

[Nikita Popov via llvm-commits]

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@@ -18,7 +18,6 @@
 #define LLVM_SUPPORT_DXILABI_H
 
 #include "llvm/ADT/StringRef.h"
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nikic wrote:

Can also replace this StringRef.h include with a forward declaration.

https://github.com/llvm/llvm-project/pull/153840