crypto: caam - refactor ahash_done callbacks

Create two common ahash_done_* functions with the dma
direction as parameter. Then, these 2 are called with
the proper direction for unmap.

Signed-off-by: Iuliana Prodan <iuliana.prodan@nxp.com>
Reviewed-by: Horia Geanta <horia.geanta@nxp.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>