armv8 SHA-1 using ARMv8 Crypto Extensions:

This patch adds support for the SHA-1 Secure Hash Algorithm for CPUs
that have support for the SHA-1 part of the ARM v8 Crypto Extensions.

It greatly improves sha-1 based operations, about 10x faster on iMX8M
evk board. ~12ms vs ~165ms for a 20MiB kernel sha-1 verification.

asm implementation is a simplified version of the Linux version (from
Ard Biesheuvel).

Signed-off-by: Loic Poulain <loic.poulain@linaro.org>