sfc: Use explicit bool for boolean variables, parameters and return values

Replace (cond ? 1 : 0) with cond or !!cond as appropriate, and
(cond ? 0 : 1) with !cond.

Remove some redundant boolean temporaries.

Rename one field that looks like a flag but isn't.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
diff --git a/drivers/net/sfc/ethtool.c b/drivers/net/sfc/ethtool.c
index ccd82f1..6142c3a 100644
--- a/drivers/net/sfc/ethtool.c
+++ b/drivers/net/sfc/ethtool.c
@@ -447,7 +447,7 @@
 	/* No way to stop the hardware doing the checks; we just
 	 * ignore the result.
 	 */
-	efx->rx_checksum_enabled = (enable ? 1 : 0);
+	efx->rx_checksum_enabled = !!enable;
 
 	return 0;
 }
@@ -641,9 +641,9 @@
 {
 	struct efx_nic *efx = netdev_priv(net_dev);
 
-	pause->rx_pause = (efx->flow_control & EFX_FC_RX) ? 1 : 0;
-	pause->tx_pause = (efx->flow_control & EFX_FC_TX) ? 1 : 0;
-	pause->autoneg = (efx->flow_control & EFX_FC_AUTO) ? 1 : 0;
+	pause->rx_pause = !!(efx->flow_control & EFX_FC_RX);
+	pause->tx_pause = !!(efx->flow_control & EFX_FC_TX);
+	pause->autoneg = !!(efx->flow_control & EFX_FC_AUTO);
 }