math/ggobi: Add missing dependency

Fixes the following breakage:

> Configuring for ggobi-2.1.12

Can't exec "autopoint": No such file or directory at /usr/local/share/autoconf2.72/Autom4te/FileUtils.pm line 318.
autoreconf2.72: error: autopoint failed with exit status: 2

> Mk/Uses/autoreconf.mk: Error running /usr/local/bin/autoreconf2.72

Reported by: pkg-fallout

MFH: 2024Q3