s390/pkey: fix PKEY_TYPE_EP11_AES handling in PKEY_CLR2SECK2 IOCTL

Commit 'fa6999e3 ("s390/pkey: support CCA and EP11 secure ECC
private keys")' introduced PKEY_TYPE_EP11_AES for the PKEY_CLR2SECK2
IOCTL to convert an AES clearkey into a securekey of this type.
Unfortunately, all PKEY_CLR2SECK2 IOCTL requests with type
PKEY_TYPE_EP11_AES return with an error (-EINVAL). Fix the handling
for PKEY_TYPE_EP11_AES in PKEY_CLR2SECK2 IOCTL, so that userspace can
convert clearkey blobs into PKEY_TYPE_EP11_AES securekey blobs.

Cc: stable@vger.kernel.org # v5.10+
Fixes: fa6999e3 ("s390/pkey: support CCA and EP11 secure ECC private keys")
Signed-off-by: Holger Dengler <dengler@linux.ibm.com>
Reviewed-by: Ingo Franzki <ifranzki@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>