wayland: Guarantee dnd-move as a cursor name

We need to go back to using this, since move is widely abused
and thus can't change its image to one thats appropriate for dnd.

gdk/wayland/gdkcursor-wayland.c

@@ -79,6 +79,7 @@ static const struct {
   { "move",         "dnd-move" },
   { "no-drop",      "dnd-none" },
   { "dnd-ask",      "dnd-copy" }, /* not CSS, but we want to guarantee it anyway */
+  { "dnd-move",     "default" },
   { "not-allowed",  "crossed_circle" },
   { "grab",         "hand2" },
   { "grabbing",     "hand2" },