crypto: marvell/cesa - Use dma_pool_zalloc

Dma_pool_zalloc combines dma_pool_alloc and memset 0.  The semantic patch
that makes this transformation is as follows: (http://coccinelle.lip6.fr/)

// <smpl>
@@
expression d,e;
statement S;
@@

        d =
-            dma_pool_alloc
+            dma_pool_zalloc
             (...);
        if (!d) S
-       memset(d, 0, sizeof(*d));
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Acked-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>