mii: Simplify mii_resolve_flowctrl_fdx()

This is a shorter and more comprehensible formulation of the
conditions for each flow control mode.
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/linux/mii.h

@@ -250,18 +250,12 @@ static inline u8 mii_resolve_flowctrl_fdx(u16 lcladv, u16 rmtadv)
 {
 	u8 cap = 0;
 
-	if (lcladv & ADVERTISE_PAUSE_CAP) {
-		if (lcladv & ADVERTISE_PAUSE_ASYM) {
-			if (rmtadv & LPA_PAUSE_CAP)
+	if (lcladv & rmtadv & ADVERTISE_PAUSE_CAP) {
 		cap = FLOW_CTRL_TX | FLOW_CTRL_RX;
-			else if (rmtadv & LPA_PAUSE_ASYM)
+	} else if (lcladv & rmtadv & ADVERTISE_PAUSE_ASYM) {
+		if (lcladv & ADVERTISE_PAUSE_CAP)
 			cap = FLOW_CTRL_RX;
-		} else {
-			if (rmtadv & LPA_PAUSE_CAP)
-				cap = FLOW_CTRL_TX | FLOW_CTRL_RX;
-		}
-	} else if (lcladv & ADVERTISE_PAUSE_ASYM) {
-		if ((rmtadv & LPA_PAUSE_CAP) && (rmtadv & LPA_PAUSE_ASYM))
+		else if (rmtadv & ADVERTISE_PAUSE_CAP)
 			cap = FLOW_CTRL_TX;
 	}