nfc: s3fwrn5: Fix potential memory leak in s3fwrn5_nci_send()

s3fwrn5_nci_send() won't free the skb when it failed for the check
before s3fwrn5_write(). As the result, the skb will memleak. Free the
skb when the check failed.

Fixes: c04c674f ("nfc: s3fwrn5: Add driver for Samsung S3FWRN5 NFC Chip")
Signed-off-by: Shang XiaoJing <shangxiaojing@huawei.com>
Suggested-by: Pavel Machek <pavel@denx.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/nfc/s3fwrn5/core.c

@@ -105,6 +105,7 @@ static int s3fwrn5_nci_send(struct nci_dev *ndev, struct sk_buff *skb)
 	mutex_lock(&info->mutex);
 
 	if (s3fwrn5_get_mode(info) != S3FWRN5_MODE_NCI) {
+		kfree_skb(skb);
 		mutex_unlock(&info->mutex);
 		return -EINVAL;
 	}