add some macros to check cpuinfo

This is a preparation patch.

Signed-off-by: Liu Yuan <namei.unix@gmail.com>
Signed-off-by: MORITA Kazutaka <morita.kazutaka@lab.ntt.co.jp>
sha1: add x86 hardware acceleration for sha1

This doesn't change the sha1 algorithm. This patch tries to make use of intel's
ssse3 and avx for sha1 acceleration.

Signed-off-by: Liu Yuan <namei.unix@gmail.com>
Signed-off-by: MORITA Kazutaka <morita.kazutaka@lab.ntt.co.jp>