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

s3fwrn5_nci_send() will call s3fwrn5_i2c_write() or s3fwrn82_uart_write(),
and free the skb if write() failed. However, even if the write() run
succeeds, the skb will not be freed in write(). As the result, the skb
will memleak. s3fwrn5_nci_send() should also free the skb when write()
succeeds.

Fixes: c04c674f

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