bug#40699: "dist Hook" documentation in manual is incorrect or unclear about write...

bug#40699: "dist Hook" documentation in manual is incorrect or unclear about write permissions

On 2020-04-20 14:59:00 -0600, Karl Berry wrote:
>     i.e. it does not change the permissions in order to make the removal
>     work recursively
>
> Right, I see it now. Had been testing the wrong thing.
>
> So, can you propose a specific change for the manual? -k

I think that it is sufficient to fix the example (the explanation
is just below). BTW, the second example is also incorrect.

commit a639e5b51cadbaff88ca4059b4db4571c811070c
Author: Vincent Lefevre <vincent@vinc17.net>
Date:   2020-04-23 17:33:54 +0200

    doc: fix dist-hook examples