bug#58843: Print "decrypted" rot13 text is buffer is read-only

[Eli Zaretskii <eliz@gnu.org>]

> From: Philip Kaludercic <philipk@posteo.net>
> Cc: 58843@debbugs.gnu.org
> Date: Sat, 29 Oct 2022 16:25:07 +0000
> 
> > No, this is described in the "Rmail Rot13" node.
> 
> Ah yes.  How does this look like:

OK, with two nits:

> +@findex rot13-region
> +  If you are only interested in a region, the command @kbd{M-x
> +rot13-region} might be preferable.  This will decrypt the active
> +region in place.  If the buffer is read-only, it will attempt to
          ^^^^^^^^
"in-place"

> +display the plain text in the echo area.  If the text is too long, a
> +separate buffer will be used.
   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Passive voice alert!  Suggest to rephrase

  If the text is too long for the echo area, the command will pop up a
  temporary buffer with the decrypted text.

Btw, is it "decrypted" or "encrypted/decrypted"?

Thanks.