[MacPorts] #52981: Print custom warnings from Portfile with `port info` (was: info phase)

[MacPorts]

#52981: Print custom warnings from Portfile with `port info`
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  Reporter:  RJVB     |      Owner:
      Type:  request  |     Status:  new
  Priority:  Normal   |  Milestone:
 Component:  base     |    Version:
Resolution:           |   Keywords:
      Port:           |
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Comment (by raimue):

 `info` is not actually a "phase" (or "target" in port1.0 terminology).
 Abusing and overriding the phase from the port client is a horrible hack.
 There is no connection between the "info" in `ui_info` and `port info` and
 there should not be any.

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Ticket URL: <https://trac.macports.org/ticket/52981#comment:2>
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