Use the number of processed bytes information (num) from the generic
cipher context for the partial block handling in cfb and ofb, instead
of keep this information in the s390x-specific part of the cipher
context. The information in the generic context is reset properly,
even if the context is re-initialized without resetting the key or iv.
Fixes: #23175
Signed-off-by: Holger Dengler <dengler@linux.ibm.com>
Reviewed-by: Shane Lontis <shane.lontis@oracle.com>
Reviewed-by: Tomas Mraz <tomas@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/23201)
