pull up r23810 from trunk

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 r23810 | tlyu | 2010-03-16 12:14:33 -0700 (Tue, 16 Mar 2010) | 8 lines

 ticket: 6685
 target_version: 1.8.1
 subject: handle NT_SRV_INST in service principal referrals

 Handle NT_SRV_INST in service principal cross-realm referrals, as
 Windows apparently uses that instead of NT_SRV_HST for at least some
 service principals.

https://github.com/krb5/krb5/commit/6d8b1c8c7f70a2da8beeea54c5d53d6085c31b79
Commit By: tlyu
Revision: 23824
Changed Files:
U   branches/krb5-1-8/src/kdc/do_tgs_req.c