crypto: sun4i-ss - do not dynamically set parts of the last buffer to 0

Parts of the bf buffer were dynamically set to 0. Change this to set the
whole buffer to 0 by default to avoid any mistake.
Signed-off-by: Antoine Tenart <antoine.tenart@free-electrons.com>
Tested-by: Corentin Labbe <clabbe.montjoie@gmail.com>
Acked-by: Corentin Labbe <clabbe.montjoie@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

drivers/crypto/sunxi-ss/sun4i-ss-hash.c

@@ -179,7 +179,7 @@ static int sun4i_hash(struct ahash_request *areq)
 	 */
 	unsigned int i = 0, end, index, padlen, nwait, nbw = 0, j = 0, todo;
 	unsigned int in_i = 0;
-	u32 spaces, rx_cnt = SS_RX_DEFAULT, bf[32], wb = 0, v, ivmode = 0;
+	u32 spaces, rx_cnt = SS_RX_DEFAULT, bf[32] = {0}, wb = 0, v, ivmode = 0;
 	struct sun4i_req_ctx *op = ahash_request_ctx(areq);
 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(areq);
 	struct sun4i_tfm_ctx *tfmctx = crypto_ahash_ctx(tfm);
@@ -417,7 +417,6 @@ static int sun4i_hash(struct ahash_request *areq)
 		zeros = (padlen - 1) / 4;
 	}
 
-	memset(bf + j, 0, 4 * zeros);
 	j += zeros;
 
 	/* write the length of data */