crypto: omap - sha1 & md5 driver

Earlier kernel contained omap sha1 and md5 driver, which was not maintained,
was not ported to new crypto APIs and removed from the source tree.

- implements async  crypto API using dma and cpu.
- supports multiple sham instances if available
- hmac
- concurrent requests

Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@nokia.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>