[MacPorts] #53925: flex: Update to 2.6.3

[MacPorts]

#53925: flex: Update to 2.6.3
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  Reporter:  pmetzger  |      Owner:
      Type:  update    |     Status:  new
  Priority:  Normal    |  Milestone:
 Component:  ports     |    Version:
Resolution:            |   Keywords:  haspatch
      Port:  flex      |
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Changes (by pmetzger):

 * Attachment "flex-Portfile.diff" added.

 diffs for Portfile

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Ticket URL: <https://trac.macports.org/ticket/53925>
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