[MacPorts] #51453: Update CImg to 1.7.1

[MacPorts]

#51453: Update CImg to 1.7.1
---------------------+--------------------------------
  Reporter:  bstj@…  |      Owner:  macports-tickets@…
      Type:  update  |     Status:  new
  Priority:  Normal  |  Milestone:
 Component:  ports   |    Version:
Resolution:          |   Keywords:  haspatch
      Port:  CImg    |
---------------------+--------------------------------

Comment (by khindenburg@…):

 see #51460 - this is his new email

-- 
Ticket URL: <https://trac.macports.org/ticket/51453#comment:4>
MacPorts <https://www.macports.org/>
Ports system for OS X