crypto: lrw - Only access common skcipher fields on spawn

As skcipher spawns may be of the type lskcipher, only the common
fields may be accessed.  This was already the case but use the
correct helpers to make this more obvious.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto/lrw.c

@@ -299,8 +299,8 @@ static void lrw_free_instance(struct skcipher_instance *inst)
 static int lrw_create(struct crypto_template *tmpl, struct rtattr **tb)
 {
 	struct crypto_skcipher_spawn *spawn;
+	struct skcipher_alg_common *alg;
 	struct skcipher_instance *inst;
-	struct skcipher_alg *alg;
 	const char *cipher_name;
 	char ecb_name[CRYPTO_MAX_ALG_NAME];
 	u32 mask;
@@ -336,13 +336,13 @@ static int lrw_create(struct crypto_template *tmpl, struct rtattr **tb)
 	if (err)
 		goto err_free_inst;
 
-	alg = crypto_skcipher_spawn_alg(spawn);
+	alg = crypto_spawn_skcipher_alg_common(spawn);
 
 	err = -EINVAL;
 	if (alg->base.cra_blocksize != LRW_BLOCK_SIZE)
 		goto err_free_inst;
 
-	if (crypto_skcipher_alg_ivsize(alg))
+	if (alg->ivsize)
 		goto err_free_inst;
 
 	err = crypto_inst_setname(skcipher_crypto_instance(inst), "lrw",
@@ -382,10 +382,8 @@ static int lrw_create(struct crypto_template *tmpl, struct rtattr **tb)
 				       (__alignof__(be128) - 1);
 
 	inst->alg.ivsize = LRW_BLOCK_SIZE;
-	inst->alg.min_keysize = crypto_skcipher_alg_min_keysize(alg) +
-				LRW_BLOCK_SIZE;
-	inst->alg.max_keysize = crypto_skcipher_alg_max_keysize(alg) +
-				LRW_BLOCK_SIZE;
+	inst->alg.min_keysize = alg->min_keysize + LRW_BLOCK_SIZE;
+	inst->alg.max_keysize = alg->max_keysize + LRW_BLOCK_SIZE;
 
 	inst->alg.base.cra_ctxsize = sizeof(struct lrw_tfm_ctx);