Trac #31148: MR51: Allow Matplotlib to use system qhull >= 7.2.0

zlscherr ([https://gitlab.com/zlscherr @zlscherr]) opened a merge
request at https://gitlab.com/sagemath/sage/-/merge_requests/51:
----
{{{
#!markdown
My system has qhull 8.0.0 installed.  Because Matplotlib
doesn't know about my system qhull it builds its own version.
This can cause runtime issues with Matplotlib trying to call
the wrong qhull library.  For example, this fixes the error that
```bash
$ ./sage -tp 8 --long src/sage/plot/plot3d/list_plot3d.py
```
produces
```bash
QH6249 qh_lib_check: Incorrect qhull library called.
Size of qhT for caller is 2896, but for library is 2792.

QH6256 qh_lib_check: Cannot continue.
Library 'qhull 7.2.0 (2015.2 2016/01/18)'
uses a static qhT (e.g., libqhull.so)
```
if the system has qhull 8.0.0 installed.
}}}

URL: https://trac.sagemath.org/31148
Reported by: galois
Ticket author(s): Zachary Scherr
Reviewer(s): Dima Pasechnik

Author: Release Manager

build/pkgs/configure/checksums.ini

@@ -1,4 +1,4 @@
 tarball=configure-VERSION.tar.gz
-sha1=d943b8d6b08af3eed1cf04271248ec330e5059b4
-md5=9ff8d31f1beed3dff6f72d4ba2c52004
-cksum=1571192709
+sha1=7a90fb55449eb88f17000adfd91518bf490983a0
+md5=466bf6926d0a4607ef027ac801d3eb58
+cksum=691624164

build/pkgs/configure/package-version.txt

@@ -1 +1 @@
-11cbcc3c2ce73c7235eb1b90041b7ecd83b5a10d
+36b6db77e28bde3f23577662ff6a03064252f758

build/pkgs/matplotlib/make-setup-config.py

@@ -1,4 +1,5 @@
 from configparser import ConfigParser
+import pkgconfig
 import os
 
 config = ConfigParser()
@@ -8,6 +9,8 @@
 
 config.add_section('libs')
 config.set('libs', 'system_freetype', 'True')
+if pkgconfig.installed('qhull', '>= 7.2.0'):
+    config.set('libs', 'system_qhull', 'True')
 # lto is problematic if we mix libraries from the OS with our own libraries,
 # which are not necessarily compiled with the same gcc version
 # https://trac.sagemath.org/ticket/27754