[PATCH] runtests: check ports on IPv6 address

[Jun Wu]

Excerpts from Augie Fackler's message of 2017-02-15 23:27:23 -0500:
> >> Heh, I reported the flakiness on #mercurial earlier today. That's why
> >> Jun sent a series of patches maybe 2 hours ago that you then queued.
> >> Have you tested with those patches applied? I have not had time to
> >> look at his patches, but maybe he should have explained their
> >> motivation better if this is indeed the same problem that I reported.
> > 
> > Or maybe I just incorrectly assumed that the problems I reported with
> > ports not being available had the same root cause as the flaky
> > test-bundle2-remote-changegroup.t?
> 
> test-bundle2-remote-changegroup.t is still flaky for me at 1ee68, which I
> believe includes the series you mentioned :/

I will investigate on gcc112. Sorry for the breakage.