net: Add ethtool to mii advertisment conversion helpers

Translating between ethtool advertisement settings and MII
advertisements are common operations for ethernet drivers.  This patch
adds a set of helper functions that implements the conversion.  The
patch then modifies a couple of the drivers to use the new functions.

Signed-off-by: Matt Carlson <mcarlson@broadcom.com>
Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ethernet/sun/niu.c b/drivers/net/ethernet/sun/niu.c
index 3ebeb9d..9997be5 100644
--- a/drivers/net/ethernet/sun/niu.c
+++ b/drivers/net/ethernet/sun/niu.c
@@ -1151,19 +1151,8 @@
 		supported |= SUPPORTED_1000baseT_Full;
 	lp->supported = supported;
 
-	advertising = 0;
-	if (advert & ADVERTISE_10HALF)
-		advertising |= ADVERTISED_10baseT_Half;
-	if (advert & ADVERTISE_10FULL)
-		advertising |= ADVERTISED_10baseT_Full;
-	if (advert & ADVERTISE_100HALF)
-		advertising |= ADVERTISED_100baseT_Half;
-	if (advert & ADVERTISE_100FULL)
-		advertising |= ADVERTISED_100baseT_Full;
-	if (ctrl1000 & ADVERTISE_1000HALF)
-		advertising |= ADVERTISED_1000baseT_Half;
-	if (ctrl1000 & ADVERTISE_1000FULL)
-		advertising |= ADVERTISED_1000baseT_Full;
+	advertising = mii_adv_to_ethtool_100bt(advert);
+	advertising |= mii_adv_to_ethtool_1000T(ctrl1000);
 
 	if (bmcr & BMCR_ANENABLE) {
 		int neg, neg1000;