netpoll: Use 'bool' for netpoll_rx() return type.

#ifdef CONFIG_NETPOLL

static inline int netpoll_rx(struct sk_buff *skb)

static inline bool netpoll_rx(struct sk_buff *skb)

{

	struct netpoll_info *npinfo = skb->dev->npinfo;

	unsigned long flags;

	int ret = 0;

	bool ret = false;

	if (!npinfo || (list_empty(&npinfo->rx_np) && !npinfo->rx_flags))

		return 0;

		return false;

	spin_lock_irqsave(&npinfo->rx_lock, flags);

	/* check rx_flags again with the lock held */

	if (npinfo->rx_flags && __netpoll_rx(skb))

		ret = 1;

		ret = true;

	spin_unlock_irqrestore(&npinfo->rx_lock, flags);

	return ret;