s390/crypto: Support for SHA3 via CPACF (MSA6)

This patch introduces sha3 support for s390.

- Rework the s390-specific SHA1 and SHA2 related code to
  provide the basis for SHA3.
- Provide two new kernel modules sha3_256_s390 and
  sha3_512_s390 together with new kernel options.

Signed-off-by: Joerg Schmidbauer <jschmidb@de.ibm.com>
Reviewed-by: Ingo Franzki <ifranzki@linux.ibm.com>
Reviewed-by: Harald Freudenberger <freude@linux.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>