fixed socket wrapper to determine family from the right structure

fixed socket wrapper to determine family from the right structure

In convert_in_un_remote() the socket family can be accessed either as
si->family or inaddr->sa_family. We were using the si->family to
determine how to cast the inaddr structure, but if si->family !=
inaddr->sa_family then we will incorrectly be casting a in6 structure
as in4 or vice-versa.