Modernise code to use override specifier

Generated by clang-tidy, with IgnoreDestructors option enabled.

Test: m checkbuild
Bug: 116509795
Change-Id: I5dafa10c2cf605165581b8cf7dd2633ed101ed65
diff --git a/compiler/utils/arm64/assembler_arm64.h b/compiler/utils/arm64/assembler_arm64.h
index fdecab8..9e01a70 100644
--- a/compiler/utils/arm64/assembler_arm64.h
+++ b/compiler/utils/arm64/assembler_arm64.h
@@ -81,7 +81,7 @@
   const uint8_t* CodeBufferBaseAddress() const override;
 
   // Copy instructions out of assembly buffer into the given region of memory.
-  void FinalizeInstructions(const MemoryRegion& region);
+  void FinalizeInstructions(const MemoryRegion& region) override;
 
   void LoadRawPtr(ManagedRegister dest, ManagedRegister base, Offset offs);