crypto: amlogic - Use kmemdup in meson_aes_setkey()

Use kmemdup rather than duplicating its implementation
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Acked-by: Corentin Labbe <clabbe@baylibre.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

drivers/crypto/amlogic/amlogic-gxl-cipher.c

@@ -372,10 +372,9 @@ int meson_aes_setkey(struct crypto_skcipher *tfm, const u8 *key,
 		kfree(op->key);
 	}
 	op->keylen = keylen;
-	op->key = kmalloc(keylen, GFP_KERNEL | GFP_DMA);
+	op->key = kmemdup(key, keylen, GFP_KERNEL | GFP_DMA);
 	if (!op->key)
 		return -ENOMEM;
-	memcpy(op->key, key, keylen);
 
 	return crypto_sync_skcipher_setkey(op->fallback_tfm, key, keylen);
 }