krb5: fix Multi-realm KDC null deref
This update fixes the following security issue with krb5:
- bnc#849240, CVE-2013-1418: fix Multi-realm KDC null deref
- Submitted by Stefan Lijewski (lijews)
Fixed bugs
bnc#849240
VUL-0: CVE-2013-1418: krb5: multi-realm KDC null dereference leads to crash