(_krb5_AES_string_to_default_iterator): set to 4096 as described in
aes draft -04
(derive_key): always remove the key->schedule since its
will contain the wrong (parent key) info
git-svn-id: svn://svn.h5l.se/heimdal/trunk/heimdal@12382 ec53bebd-3082-4978-b11e-865c3cabbd6b