nfc: fix potential illegal memory access

The frags_q is not properly initialized, it may result in illegal memory
access when conn_info is NULL.
The "goto free_exit" should be replaced by "goto exit".

Signed-off-by: Yang Wei <[e-mail]>
Signed-off-by: David S. Miller <[e-mail]>

net/nfc/nci/data.c

···
 	conn_info = nci_get_conn_info_by_conn_id(ndev, conn_id);
 	if (!conn_info) {
 		rc = -EPROTO;
-		goto free_exit;
+		goto exit;
 	}
 
 	__skb_queue_head_init(&frags_q);