net: drivers: use bool type instead of double negation

Save some punctuation by using bool type's property equivalent to
doubled negation operator.
Reported-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/jme.c

@@ -1883,7 +1883,7 @@ jme_fill_tx_map(struct pci_dev *pdev,
 		struct page *page,
 		u32 page_offset,
 		u32 len,
-		u8 hidma)
+		bool hidma)
 {
 	dma_addr_t dmaaddr;
 
@@ -1917,7 +1917,7 @@ jme_map_tx_skb(struct jme_adapter *jme, struct sk_buff *skb, int idx)
 	struct jme_ring *txring = &(jme->txring[0]);
 	struct txdesc *txdesc = txring->desc, *ctxdesc;
 	struct jme_buffer_info *txbi = txring->bufinf, *ctxbi;
-	u8 hidma = !!(jme->dev->features & NETIF_F_HIGHDMA);
+	bool hidma = jme->dev->features & NETIF_F_HIGHDMA;
 	int i, nr_frags = skb_shinfo(skb)->nr_frags;
 	int mask = jme->tx_ring_mask;
 	const struct skb_frag_struct *frag;

drivers/net/ethernet/marvell/mv643xx_eth.c

@@ -1582,7 +1582,7 @@ static int
 mv643xx_eth_set_features(struct net_device *dev, netdev_features_t features)
 {
 	struct mv643xx_eth_private *mp = netdev_priv(dev);
-	int rx_csum = !!(features & NETIF_F_RXCSUM);
+	bool rx_csum = features & NETIF_F_RXCSUM;
 
 	wrlp(mp, PORT_CONFIG, rx_csum ? 0x02000000 : 0x00000000);
 

drivers/net/ethernet/marvell/sky2.c

@@ -4313,7 +4313,7 @@ static int sky2_set_features(struct net_device *dev, netdev_features_t features)
 	netdev_features_t changed = dev->features ^ features;
 
 	if (changed & NETIF_F_RXCSUM) {
-		int on = !!(features & NETIF_F_RXCSUM);
+		bool on = features & NETIF_F_RXCSUM;
 		sky2_write32(sky2->hw, Q_ADDR(rxqaddr[sky2->port], Q_CSR),
 			     on ? BMU_ENA_RX_CHKSUM : BMU_DIS_RX_CHKSUM);
 	}

drivers/net/xen-netfront.c

@@ -201,9 +201,9 @@ static void xennet_sysfs_delif(struct net_device *netdev);
 #define xennet_sysfs_delif(dev) do { } while (0)
 #endif
 
-static int xennet_can_sg(struct net_device *dev)
+static bool xennet_can_sg(struct net_device *dev)
 {
-	return !!(dev->features & NETIF_F_SG);
+	return dev->features & NETIF_F_SG;
 }