clean up dead x86 filter opts code

src/core/SkBitmapProcState.h

Index: src/core/SkBitmapProcState.h
diff --git a/src/core/SkBitmapProcState.h b/src/core/SkBitmapProcState.h
index 34f70c55e79cc5c14c83cf1450d622553072e781..87bee35a252fb4b186d4f5fc3d1a5d37e36b6cfa 100644
--- a/src/core/SkBitmapProcState.h
+++ b/src/core/SkBitmapProcState.h
@@ -187,10 +187,6 @@ void ClampX_ClampY_filter_affine(const SkBitmapProcState& s,
                                  uint32_t xy[], int count, int x, int y);
 void ClampX_ClampY_nofilter_affine(const SkBitmapProcState& s,
                                    uint32_t xy[], int count, int x, int y);
-void S32_D16_filter_DX(const SkBitmapProcState& s,
-                       const uint32_t* xy, int count, uint16_t* colors);
-void S32_D16_filter_DXDY(const SkBitmapProcState& s,
-                         const uint32_t* xy, int count, uint16_t* colors);
 
 // Helper class for mapping the middle of pixel (x, y) into SkFractionalInt bitmap space.
 // TODO: filtered version which applies a fFilterOne{X,Y}/2 bias instead of epsilon?