vcl: hide bitmap helpers in an anonymous namespace.

Change-Id: I96ad50f538cfb6ecd256c4268feb81796a135b2b

vcl/source/bitmap/bitmapscalesuper.cxx

@@ -22,6 +22,8 @@
 
 #include <boost/scoped_array.hpp>
 
+namespace {
+
 #define MAP( cVal0, cVal1, nFrac )  ((sal_uInt8)((((long)(cVal0)<<7L)+nFrac*((long)(cVal1)-(cVal0)))>>7L))
 
 void generateMap(long nW, long nDstW, bool bHMirr, long* pMapIX, long* pMapFX)
@@ -931,6 +933,8 @@ void scaleNonPalleteGeneral2(BitmapReadAccess* pAcc, BitmapWriteAccess* pWAcc,
     }
 }
 
+} // end anonymous namespace
+
 BitmapScaleSuper::BitmapScaleSuper(const double& rScaleX, const double& rScaleY) :
     mrScaleX(rScaleX),
     mrScaleY(rScaleY)