nfc: Fix potential resource leaks

nfc_get_device() take reference for the device, add missing
nfc_put_device() to release it when not need anymore.
Also fix the style warnning by use error EOPNOTSUPP instead of
ENOTSUPP.

Fixes: 5ce3f32b ("NFC: netlink: SE API implementation")
Fixes: 29e76924

 ("nfc: netlink: Add capability to reply to vendor_cmd with data")
Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>