[MacPorts] #68583: balsa: update to 2.6.4

[MacPorts]

#68583: balsa: update to 2.6.4
----------------------------+----------------------
  Reporter:  contextnerror  |      Owner:  (none)
      Type:  update         |     Status:  new
  Priority:  Normal         |  Milestone:
 Component:  ports          |    Version:
Resolution:                 |   Keywords:  haspatch
      Port:  balsa          |
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Comment (by ryandesign):

 What is the purpose of patch-configure.ac.diff? I realize you're just
 updating an existing patchfile, but why is it there? What problem occurs
 if the patch is not there? It should be documented at the top of the
 patchfile, e.g. with a URL to the upstream bug report so that we can check
 on it periodically to see if upstream has fixed it.

 When this patchfile was
 [changeset:8614c3552b327a28965b4988315987156e619e72/macports-ports
 originally added], it corrected the project's version number, but upstream
 has fixed that long ago, so if this patch isn't fixing any additional
 problem, it should be removed.

-- 
Ticket URL: <https://trac.macports.org/ticket/68583#comment:1>
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