crypto: caam - fix addressing of struct member

buf_0 and buf_1 in caam_hash_state are not next to each other.
Accessing buf_1 is incorrect from &buf_0 with an offset of only
size_of(buf_0). The same issue is also with buflen_0 and buflen_1

Cc: <stable@vger.kernel.org> # 3.13+
Signed-off-by: Cristian Stoica <cristian.stoica@freescale.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

drivers/crypto/caam/caamhash.c

@@ -1417,9 +1417,9 @@ static int ahash_update_first(struct ahash_request *req)
 	struct device *jrdev = ctx->jrdev;
 	gfp_t flags = (req->base.flags & (CRYPTO_TFM_REQ_MAY_BACKLOG |
 		       CRYPTO_TFM_REQ_MAY_SLEEP)) ? GFP_KERNEL : GFP_ATOMIC;
-	u8 *next_buf = state->buf_0 + state->current_buf *
-		       CAAM_MAX_HASH_BLOCK_SIZE;
-	int *next_buflen = &state->buflen_0 + state->current_buf;
+	u8 *next_buf = state->current_buf ? state->buf_1 : state->buf_0;
+	int *next_buflen = state->current_buf ?
+		&state->buflen_1 : &state->buflen_0;
 	int to_hash;
 	u32 *sh_desc = ctx->sh_desc_update_first, *desc;
 	dma_addr_t ptr = ctx->sh_desc_update_first_dma;