Provide hardware state import/export functionality, as mandated by
commit 8996eafd ("crypto: ahash - ensure statesize is non-zero")

Cc: <stable@vger.kernel.org> # 4.3+
Reported-by: Jonas Eymann <J.Eymann@gmx.net>
Signed-off-by: Horia Geant? <horia.geanta@nxp.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>