wayland: Support the all-resize cursor

Add all-resize to the list of names that we want to guarantee.
We use move as the fallback for it. The idea is that all-resize
will be visually compatible with resize cursors, and move will
be visually compatible with dnd cursors. And it is nice to
have two distinct names, so the metaphors can be changed without
clashing.

(cherry picked from commit 79ba34f1aa82de7d06c19109582f7df5f144a6c1)

gdk/wayland/gdkcursor-wayland.c

@@ -122,6 +122,7 @@ static const struct {
   { "nwse-resize",  "bd_double_arrow" },
   { "zoom-in",      "left_ptr" },
   { "zoom-out",     "left_ptr" },
+  { "all-resize",   "move" }, /* not CSS, but we want to guarantee it anyway */
   { NULL, NULL }
 };