fdo#77667 Remove gcc3 workaround

It appears from previous commit log entries that GCC 3.3 and below had
problems handling instantiated objects as parameters. Therefore, we
don't need this aNullPt, so removing it.

Change-Id: I8f88067628078e5b57ed76b8b7dfdb76baa3b2ea

vcl/source/outdev/bitmap.cxx

@@ -941,10 +941,9 @@ void OutputDevice::ImplDrawAlpha( const Bitmap& rBmp, const AlphaMask& rAlpha,
                                   const Point& rDestPt, const Size& rDestSize,
                                   const Point& rSrcPtPixel, const Size& rSrcSizePixel )
 {
-    const Point aNullPt;
     Point       aOutPt( LogicToPixel( rDestPt ) );
     Size        aOutSz( LogicToPixel( rDestSize ) );
-    Rectangle   aDstRect( aNullPt, GetOutputSizePixel() );
+    Rectangle   aDstRect( Point(), GetOutputSizePixel() );
     const bool  bHMirr = aOutSz.Width() < 0;
     const bool  bVMirr = aOutSz.Height() < 0;
 
@@ -999,7 +998,7 @@ void OutputDevice::ImplDrawAlpha( const Bitmap& rBmp, const AlphaMask& rAlpha,
 
         VirtualDevice* pOldVDev = mpAlphaVDev;
 
-        Rectangle aBmpRect( aNullPt, rBmp.GetSizePixel() );
+        Rectangle aBmpRect( Point(), rBmp.GetSizePixel() );
         if( !bNativeAlpha
                 &&  !aBmpRect.Intersection( Rectangle( rSrcPtPixel, rSrcSizePixel ) ).IsEmpty() )
         {