bug#52518: Log only vc-command-messages

[Juri Linkov <juri@linkov.net>]

close 52518 29.0.50
thanks

> Would this be simpler?
>
>     If non-nil, display and log run messages from back-end commands.
>     If `log', messages are logged to the *Messages* buffer but not
>     displayed.
>
>> +  :type '(choice (const :tag "No display and no log" nil)
>> +                 (const :tag "Display and log messages" t)
>> +                 (const :tag "Only log messages without displaying" log))
>
> Perhaps the first one could be:
>
>     No messages
>
> Perhaps the last one could be:
>
>     Log messages

Thanks for the suggestions.  Now pushed to master with all corrections.
I'm not sure if a NEWS entry is needed, since this option is useful mostly
for debugging.