bool conversion for windows, too

Change-Id: I38e481ce7d4eeea6679e33640555469cd18d3109

sfx2/source/doc/graphhelp.cxx

@@ -184,7 +184,7 @@ void* GraphicHelper::getWinMetaFileFromGDI_Impl( const GDIMetaFile* pGDIMeta, co
 bool GraphicHelper::supportsMetaFileHandle_Impl()
 {
 #ifdef WNT
-    return sal_True;
+    return true;
 #else
     return false;
 #endif