Drop PLOT option.

gnuplot completely removed support for the gnugraph and unixplot terminal
drivers in 2011. From the one of the ChangeLog files:

> 2011-05-31  Ethan A Merritt  <merritt@u.washington.edu>
> [...]
> Remove obsolete terminal drivers gnugraph and unixplot. The underlying
> gnu plotutils library is itself more than 10 years out of date (last
> release July 2000) and the terminal drivers haven't been upgraded for
> longer than that. In any event, current gnuplot has better native
> terminal drivers for the devices supported by unixplot/gnugraph.

In practice, this means the PLOT option is a no-op and the dependency on
graphics/plotutils is unnecessary. Indeed, if one looks at the port's build
logs in the cluster the following can be seen:

configure: WARNING: unrecognized options: --without-lisp-files, --with-plot,
--disable-thin-splines, --with-wx-config

PR:		205488
Approved by:	glewis (maintainer)

0 files changed, 0 insertions, 0 deletions