[HLSL] replace std::unordered_map with DenseMap

Broke some builds because of a missing include. Changing to a DenseMap
and adding the missing include.

Author: Keenuts

clang/lib/CodeGen/CGHLSLRuntime.cpp

@@ -27,6 +27,7 @@
 #include "clang/AST/Type.h"
 #include "clang/Basic/TargetOptions.h"
 #include "clang/Frontend/FrontendDiagnostic.h"
+#include "llvm/ADT/DenseMap.h"
 #include "llvm/ADT/ScopeExit.h"
 #include "llvm/ADT/SmallString.h"
 #include "llvm/ADT/SmallVector.h"
@@ -905,7 +906,7 @@ void CGHLSLRuntime::emitEntryFunction(const FunctionDecl *FD,
     OB.emplace_back("convergencectrl", bundleArgs);
   }
 
-  std::unordered_map<const DeclaratorDecl *, llvm::Value *> OutputSemantic;
+  llvm::DenseMap<const DeclaratorDecl *, llvm::Value *> OutputSemantic;
 
   unsigned SRetOffset = 0;
   for (const auto &Param : Fn->args()) {