bug#62207: 29.0.60; Trying to remove non-existent key binding instead adds a binding

[Eli Zaretskii]

> From: Robert Pluim <rpluim@gmail.com>
> Cc: 62207@debbugs.gnu.org,  larsi@gnus.org,  jonas@bernoul.li,  Stefan
>  Monnier <monnier@iro.umontreal.ca>
> Date: Fri, 17 Mar 2023 10:55:23 +0100
> 
> `keymap-unset' is also not documented in the lisp reference
> manual. How about this?
> 
> @findex keymap-unset
> @defun keymap-unset keymap key &optional remove
> This function is the inverse of @code{keymap-set}, it unsets the
> binding for @var{key} in @var{keymap}, which is the same as setting
> the binding to @code{nil}.  In order to instead remove the binding
> completely, specify @var{remove} as non-nil.  This only makes a
> difference if @var{keymap} has a parent keymap.  When unsetting a key
> in a child map, it will still shadow the same key in the parent
> keymap.  Removing the binding will allow the key in the parent keymap
> to be used.

LGTM, thanks.