crypto: artpec6 - Fix printk warning on size_t/%d

Switch to %zu instead of %d for printing size_t.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

drivers/crypto/axis/artpec6_crypto.c

@@ -1712,7 +1712,7 @@ static int artpec6_crypto_prepare_crypto(struct skcipher_request *areq)
 		cipher_len = regk_crypto_key_256;
 		break;
 	default:
-		pr_err("%s: Invalid key length %d!\n",
+		pr_err("%s: Invalid key length %zu!\n",
 			MODULE_NAME, ctx->key_length);
 		return -EINVAL;
 	}