bug#61183: 29.0.60; Add describe-repeat-maps to the manual

[Juri Linkov <juri@linkov.net>]

>> How about putting something like
>>
>> If `repeat-mode' is enabled, these keymaps determine which single key
>> can be used to repeat a command invoked via a full key sequence.
>>
>> in the buffer produced by `descripe-repeat-maps'?
>
> This text is much better, thanks.

Now added to the docstring.

>                                    However, it only talks about the
> keymaps, whereas the window we pop shows also some key bindings for
> each keymap.  The explanatory text should say something about that as
> well, I think.  Such an explanation would probably clarify why the
> text says "single" in "single key", which currently looks "out of the
> blue".