RFC 4120 says that we should not canonicalize using DNS. We cannot get

RFC 4120 says that we should not canonicalize using DNS. We cannot get
that far today, but there's no reason we should fail to use a
perfectly good principal name just because DNS is failing. For some
services there isn't even a requirement they be in DNS. With
AI_ADDRCONFIG there's no reason that Kerberos canonicalization should
fail simply because a v6 address is not present, for example.  So, if
getaddrinfo fails in krb5_sname_to_principal simply use the input
hostname uncanonicalized.

sn2princ: On getaddrinfo failure use the input

git-svn-id: svn://anonsvn.mit.edu/krb5/trunk@25357 dc483132-0cff-0310-8789-dd5450dbe970