We had:
auto ipv4 = (struct sockaddr_in *)&clientInfo.sin_addr
even if the clientInfo variable itself was a struct sockaddr_in.
And then we also had:
auto ipv6 = (struct sockaddr_in6 *)&clientInfo.sin_addr
which makes even less sense.
Instead, make clientInfo into a struct sockaddr_in6, which is big
enough to also to be interpreted as a sockaddr_in. Pass the address of
the correct field, either sin_addr or sin6_addr, to inet_ntop(). (Note
that sin_addr in sockaddr_in has a different offset than sin6_addr in
sockaddr_in6.)
At least on my Fedora 28, when I connect using IPv4, accept4() still
returns the client address as an IPv4 mapped IPv6 address, that is
::ffff:192.168.1.113 for 192.168.1.113. So the sample
net.post_allow.host value in loolwsd.xml.in should probably be changed
to have that ::ffff: prefix, too.
Change-Id: I0ad774616b210d94b904982e2f7dc928adc879ed
a97c8c3455