s390x: AES OFB/CFB: Maintain running IV from cipher context

s390x: AES OFB/CFB: Maintain running IV from cipher context

Copy the current IV from the cipher context into the kmo/kmf param before
the operation, and copy the modified IV back to the context afterwards.
Without this, an application that obtains the running IV from the context
would still get the original IV, but not the updated one.

Signed-off-by: Ingo Franzki <ifranzki@linux.ibm.com>
Reviewed-by: Patrick Steuer <patrick.steuer@de.ibm.com>
Reviewed-by: Tomas Mraz <tomas@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/16292)