ITS#7694 Fix use of IPv6 with LDAP_CONNECTIONLESS

ITS#7694 Fix use of IPv6 with LDAP_CONNECTIONLESS

LDAP_CONNECTIONLESS code assumed that the size of an peer address
is equal to or smaller than sizeof (struct sockaddr).

Fix to use struct sockaddr_storage instead which is intended for
this purpose. Use getnameinfo() where appropriate so we don't
assume anything about the contents of struct sockaddr