pull up r24481 from trunk

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 r24481 | ghudson | 2010-10-25 16:17:54 -0400 (Mon, 25 Oct 2010) | 7 lines

 ticket: 6796
 target_version: 1.9
 tags: pullup

 Use safer output parameter handling in
 krb5_gss_acquire_cred_impersonate_name and its subsidiary helpers.

https://github.com/krb5/krb5/commit/f81030c8386e20914d027d07a9991ae879987ae0
Commit By: tlyu
Revision: 24499
Changed Files:
U   branches/krb5-1-9/src/lib/gssapi/krb5/s4u_gss_glue.c