bug#46369: [External] : bug#46369: 28.0.50; Bind clone-buffer into the new C-x x keymap

[Drew Adams]

> I noticed that Lars has bound rename-uniquely to C-x x u.
> 
> I find that clone-buffer is a useful companion command to
> rename-uniquely so would like to request binding C-x x n to that (the
> letter 'n' follows Info-mode binding it to M-n).

Please refrain from binding keys by default to
prefix key `C-x x'.