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>
diff --git a/drivers/net/ethernet/marvell/sky2.c b/drivers/net/ethernet/marvell/sky2.c
index c79dc54..7db6e36 100644
--- a/drivers/net/ethernet/marvell/sky2.c
+++ b/drivers/net/ethernet/marvell/sky2.c
@@ -4313,7 +4313,7 @@
 	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);
 	}