ecore_wl2: Fix buffer manager refcounting

commit 0cf806005e correctly fixed a
leaked buffer.  However, other code was already accounting for the
leaked reference to the buffer manager, so an extra deref happened
and broke the universe - but only on hardware that no developer
has access to for testing.

src/lib/ecore_wl2/ecore_wl2_buffer.c

@@ -583,7 +583,6 @@ _create_failed(void *data, struct zwp_linux_buffer_params_v1 *params)
    Ecore_Wl2_Display *ewd = data;
 
    zwp_linux_buffer_params_v1_destroy(params);
-   _buffer_manager_deref();
    _buffer_manager_destroy();
    ewd->wl.dmabuf = NULL;
 }