Fixed RtlCompareString and RtlCompareStringN, they were very wrong, for CompareString the params are struct ptrs not char ptrs

Fixed a ton of clang-cl compiler warnings about unused variables, still many left. Fixed a lot of inconsistent override ones too

src/xenia/gpu/d3d12/d3d12_command_processor.cc

@@ -5152,6 +5152,7 @@ void D3D12CommandProcessor::WriteGammaRampSRV(
 #define COMMAND_PROCESSOR D3D12CommandProcessor
 
 #include "../pm4_command_processor_implement.h"
+#undef COMMAND_PROCESSOR
 }  // namespace d3d12
 }  // namespace gpu
 }  // namespace xe

src/xenia/gpu/d3d12/d3d12_command_processor.h

@@ -50,8 +50,9 @@ struct MemExportRange {
 };
 class D3D12CommandProcessor final : public CommandProcessor {
  protected:
+#define OVERRIDING_BASE_CMDPROCESSOR
 #include "../pm4_command_processor_declare.h"
-
+#undef OVERRIDING_BASE_CMDPROCESSOR
  public:
   explicit D3D12CommandProcessor(D3D12GraphicsSystem* graphics_system,
                                  kernel::KernelState* kernel_state);

src/xenia/gpu/d3d12/d3d12_texture_cache.h

@@ -87,7 +87,7 @@ class D3D12TextureCache final : public TextureCache {
 
   ~D3D12TextureCache();
 
-  void ClearCache();
+  void ClearCache() override;
 
   void BeginSubmission(uint64_t new_submission_index) override;
   void BeginFrame() override;