ksz884x: fix Endian

ETH_P_IP is host Endian, skb->protocol is big Endian, when
compare them, Using htons on skb->protocol is wrong.

And fix two code style issues: indentation and remove
unnecessary parentheses.

CC: Tristram Ha <Tristram.Ha@micrel.com>
CC: Ben Hutchings <bhutchings@solarflare.com>
CC: Joe Perches <joe@perches.com>
Signed-off-by: Li RongQing <roy.qing.li@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/micrel/ksz884x.c

@@ -4879,8 +4879,8 @@ static netdev_tx_t netdev_tx(struct sk_buff *skb, struct net_device *dev)
 	left = hw_alloc_pkt(hw, skb->len, num);
 	if (left) {
 		if (left < num ||
-				((CHECKSUM_PARTIAL == skb->ip_summed) &&
-				(ETH_P_IPV6 == htons(skb->protocol)))) {
+		    (CHECKSUM_PARTIAL == skb->ip_summed &&
+		     skb->protocol == htons(ETH_P_IPV6))) {
 			struct sk_buff *org_skb = skb;
 
 			skb = netdev_alloc_skb(dev, org_skb->len);