[krbdev.mit.edu #8426] test_check_allowed_to_delegate() should free unparsed princ output

[Will Fiveash via RT]

In test_check_allowed_to_delegate() there is:

    check(krb5_unparse_name_flags(context, server->princ,
                                  KRB5_PRINCIPAL_UNPARSE_NO_REALM,
&sprinc));
    check(krb5_unparse_name_flags(context, proxy,
                                  KRB5_PRINCIPAL_UNPARSE_NO_REALM,
&tprinc));

but because this function does not free sprinc/tprinc after those calls
memory leak checking reports leaks that are not important but this does
introduce unnecessary false positives when looking for real memory leaks
in krb5kdc.