crypto: marvell - turn mv_cesa_ahash_init() into a function returning void

The mv_cesa_ahash_init() function always returns 0, and the return
value is anyway never checked. Turn it into a function returning void.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>