[MacPorts] #58953: root6: don't default to +cocoa when +x11 is selected

[MacPorts]

#58953: root6: don't default to +cocoa when +x11 is selected
--------------------+--------------------------
 Reporter:  jmroot  |      Owner:  cjones051073
     Type:  defect  |     Status:  assigned
 Priority:  Normal  |  Milestone:
Component:  ports   |    Version:
 Keywords:          |       Port:  root6
--------------------+--------------------------
 {{{
 % port info root6 +x11
 Error: root6: Variant cocoa conflicts with x11
 Error: Unable to open port: Error evaluating variants
 }}}

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Ticket URL: <https://trac.macports.org/ticket/58953>
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