net: ethernet: sun: drop unused variable

Commit bfd428da ("net: ethernet: sun: initialize variables directly")
dropped the only loop that was using i but did not remove the actual
variable, therefore causing a warning when building. This patch drops
the now redundant line.
Reported-by: NStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NEmilio López <emilio@elopez.com.ar>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/ethernet/sun/sunbmac.c

@@ -995,7 +995,6 @@ static void bigmac_set_multicast(struct net_device *dev)
 	struct bigmac *bp = netdev_priv(dev);
 	void __iomem *bregs = bp->bregs;
 	struct netdev_hw_addr *ha;
-	int i;
 	u32 tmp, crc;
 
 	/* Disable the receiver.  The bit self-clears when