EMAC driver: Fix bug: The clock divisor is set to all ones at reset.

Signed-off-by: NKalle Pokki <kalle.pokki@eke.com>
Signed-off-by: NBryan Wu <bryan.wu@analog.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/bfin_mac.c

@@ -408,7 +408,7 @@ static int mii_probe(struct net_device *dev)
 	mdc_div = ((sclk / MDC_CLK) / 2) - 1;
 
 	sysctl = bfin_read_EMAC_SYSCTL();
-	sysctl |= SET_MDCDIV(mdc_div);
+	sysctl = (sysctl & ~MDCDIV) | SET_MDCDIV(mdc_div);
 	bfin_write_EMAC_SYSCTL(sysctl);
 
 	/* search for connect PHY device */