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

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: 0e3b45f0771d ("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>