[title]
Confirm that CPACF is enabled

[description]
The CP Assist for Cryptographic Functions (CPACF) accelerates
symmetric cryptographic algorithms.  This check verifies that
CPACF is enabled on the system.

CPACF is a mandatory prerequisite for hardware-based acceleration of
cryptographic operations in the following contexts:

 * the OpenSSL software stack (see also checks crypto_openssl_stack and
   crypto_openssl_stack_32bit)
 * the clear key openCryptoki (PKCS#11) software stack (see also checks
   crypto_opencryptoki_ckc and crypto_opencryptoki_ckc_32bit)
 * Linux kernel-internal cryptographic operations, such as dm-crypt and
   IPSec

CPACF is also required for the availability of the /dev/prng pseudo random
number generator device.

Optionally CPACF enables protected key operation for the Common Cryptographic
Architecture (CCA) software stack (see also checks crypto_cca_stack,
crypto_opencryptoki_skc, and opencryptoki_skc_32bit).
