Subzero: Emit ARM build-attributes in the file scope (as header).

src/IceTargetLoweringX8632.h

Index: src/IceTargetLoweringX8632.h
diff --git a/src/IceTargetLoweringX8632.h b/src/IceTargetLoweringX8632.h
index 577334091288c28cf61b853861cfd2d6287c14d6..c81e08156bd183ee4e1b321e404157245558ff95 100644
--- a/src/IceTargetLoweringX8632.h
+++ b/src/IceTargetLoweringX8632.h
@@ -597,6 +597,23 @@ private:
   template <typename T> static void emitConstantPool(GlobalContext *Ctx);
 };
 
+class TargetHeaderX8632 : public TargetHeaderLowering {
+  TargetHeaderX8632() = delete;
+  TargetHeaderX8632(const TargetHeaderX8632 &) = delete;
+  TargetHeaderX8632 &operator=(const TargetHeaderX8632 &) = delete;
+
+public:
+  static TargetHeaderLowering *create(GlobalContext *Ctx) {
+    return new TargetHeaderX8632(Ctx);
+  }
+
+protected:
+  explicit TargetHeaderX8632(GlobalContext *Ctx);
+
+private:
+  ~TargetHeaderX8632() final {}
+};
+
 } // end of namespace Ice
 
 #endif // SUBZERO_SRC_ICETARGETLOWERINGX8632_H