The mingw headers lack the IPV6_V6ONLY define, depending where you get
them from. Currently the headers provided by mingw-builds are more
complete than those from mingw.org itself.
I have removed the compile time check, defined the macro if it is
undefined, and it should be just a runtime check for if you are running
on windows XP you get no dual stack binding.
Task-number: QTBUG-28787
Task-number: QTBUG-28971
Task-number: QTBUG-28972
Change-Id: Iafadbb55d367c44ba9f812a24115e65591701b54
Reviewed-by: Ilya Sidorov
Reviewed-by: Peter Hartmann <phartmann@rim.com>
(cherry picked from commit d3c4296198)
e3bd06426a