crypto: starfive - fix return value check in starfive_aes_prepare_req()

kzalloc() returns NULL pointer not PTR_ERR() when it fails,
so replace the IS_ERR() check with NULL pointer check.

Fixes: e22471c233 ("crypto: starfive - Add AES skcipher and aead support")
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

drivers/crypto/starfive/jh7110-aes.c

@@ -496,8 +496,8 @@ static int starfive_aes_prepare_req(struct skcipher_request *req,
 
 	if (cryp->assoclen) {
 		rctx->adata = kzalloc(ALIGN(cryp->assoclen, AES_BLOCK_SIZE), GFP_KERNEL);
-		if (IS_ERR(rctx->adata))
-			return dev_err_probe(cryp->dev, PTR_ERR(rctx->adata),
+		if (!rctx->adata)
+			return dev_err_probe(cryp->dev, -ENOMEM,
 					     "Failed to alloc memory for adata");
 
 		scatterwalk_copychunks(rctx->adata, &cryp->in_walk, cryp->assoclen, 0);