[MacPorts] #54314: gfbgraph: Fix license

[MacPorts]

#54314: gfbgraph: Fix license
------------------------+------------------------
 Reporter:  ryandesign  |      Owner:  juanrgar@…
     Type:  defect      |     Status:  new
 Priority:  Normal      |  Milestone:
Component:  ports       |    Version:
 Keywords:              |       Port:  gfbgraph
------------------------+------------------------
 The port claims to be licensed under "GPL-2.1". There is a GPL 2, and
 there is an LGPL 2.1, but there is no GPL 2.1. Please clarify the license.

--
Ticket URL: <https://trac.macports.org/ticket/54314>
MacPorts <https://www.macports.org/>
Ports system for macOS