nfc: nxp-nci: Fix potential memory leak in nxp_nci_send()

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

Fixes: dece4585

 ("NFC: nxp-nci: Add support for NXP NCI chips")
Signed-off-by: Shang XiaoJing <shangxiaojing@huawei.com>
Suggested-by: Pavel Machek <pavel@denx.de>
Signed-off-by: David S. Miller <davem@davemloft.net>