Remove comment from patch that doesn't apply anymore

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@42885 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/common/dcbufcmn.cpp

@@ -55,8 +55,6 @@ public:
             delete ms_buffer;
             ms_buffer = new wxBitmap(w, h);
         }
-
-        // return a copy of the static instance
         return ms_buffer;
     }