net: ethernet: sun: remove redundant variables adv and lpa and mii_reads

Variables adv and lpa are being assigned but are never used hence they
are redundant and can be removed.  Also remove the unncessary mii_reads
too.

Cleans up clang warnings:
warning: variable 'lpa' set but not used [-Wunused-but-set-variable]
warning: variable 'adv' set but not used [-Wunused-but-set-variable]
Signed-off-by: NColin Ian King <colin.king@canonical.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/ethernet/sun/niu.c

@@ -1225,25 +1225,9 @@ static int link_status_1g_rgmii(struct niu *np, int *link_up_p)
 
 	bmsr = err;
 	if (bmsr & BMSR_LSTATUS) {
-		u16 adv, lpa;
-
-		err = mii_read(np, np->phy_addr, MII_ADVERTISE);
-		if (err < 0)
-			goto out;
-		adv = err;
-
-		err = mii_read(np, np->phy_addr, MII_LPA);
-		if (err < 0)
-			goto out;
-		lpa = err;
-
-		err = mii_read(np, np->phy_addr, MII_ESTATUS);
-		if (err < 0)
-			goto out;
 		link_up = 1;
 		current_speed = SPEED_1000;
 		current_duplex = DUPLEX_FULL;
-
 	}
 	lp->active_speed = current_speed;
 	lp->active_duplex = current_duplex;