gss_krb5_ccache_name can return pointer to freed memory

[Ezra Peisach]

Further investigation - shows that this has already been reported as a
bug (#1235) and IBM has incorporated an API documentation
(www.tu-darmstadt.de/hrz/unix/ibm/ documentation/krb5/APDEVREF.HTM )
indicating that the memory should be freed by the caller.

I saw one reference to some using gss_krb5_ccache_name in some sort
of plugin - but no source to see usage...

I am leaning towards the strdup solution with the user freeing storage.

  Ezra