use wxStockCursor (as documented and as already implemented in wxMotif) instead of a plain 'int'

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@55837 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/gtk/cursor.cpp

@@ -56,7 +56,7 @@ wxCursor::wxCursor()
 {
 }
 
-wxCursor::wxCursor( int cursorId )
+wxCursor::wxCursor( wxStockCursor cursorId )
 {
     m_refData = new wxCursorRefData();