bug#30349: 27.0.50; Cuonfusing documentation about pipe processes

[Eli Zaretskii]

> From: Noam Postavsky <npostavs@users.sourceforge.net>
> Date: Tue, 6 Feb 2018 19:05:54 -0500
> Cc: Philipp Stephani <p.stephani2@gmail.com>, 30349@debbugs.gnu.org
> 
> Hmm, I know I have a personal tendency for terseness, but that really
> seems redundant to me:
> 
>     :buffer BUFFER -- BUFFER is the buffer (or buffer-name) to associate
>     with the process.  Process output goes at end of that buffer, unless
>     you specify a filter function to handle the output.  The default
>     filter function writes process output at the end of that buffer. [...]

You are right, it is redundant.