crypto: sha512-mb - Algorithm data structures

This patch introduces the data structures and prototypes of functions
needed for computing SHA512 hash using multi-buffer. Included are the
structures of the multi-buffer SHA512 job, job scheduler in C and x86
assembly.

Signed-off-by: Megha Dey <megha.dey@linux.intel.com>
Reviewed-by: Fenghua Yu <fenghua.yu@intel.com>
Reviewed-by: Tim Chen <tim.c.chen@linux.intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>