Remove ksu's own implementation of krb5_verify_init_creds now that it is not used.

https://github.com/krb5/krb5/commit/1fd7ca9fe9c756155e9944916826147bab6f167b
Commit By: hartmans
Revision: 21715
Changed Files:
U   trunk/src/clients/ksu/krb_auth_su.c