werror: declaration of 'nWidth' hides previous declaration

Change-Id: Ida3b031f0425aae8d8372410311312b4d7a13d2f
Reviewed-on: https://gerrit.libreoffice.org/22683Reviewed-by: Stephan Bergmann <sbergman@redhat.com>
Tested-by: Stephan Bergmann <sbergman@redhat.com>

canvas/source/directx/dx_vcltools.cxx

@@ -201,8 +201,6 @@ namespace dxcanvas
                                       "Unsupported alpha scanline format" );
 
                     BitmapColor     aCol;
-                    const sal_Int32 nWidth( aBmpSize.Width() );
-                    const sal_Int32 nHeight( aBmpSize.Height() );
                     sal_uInt8*      pCurrOutput( aBmpData.mpBitmapData.get() );
                     int             x, y;