m68knommu: correct the mii calculations for 532x ColdFire FEC

Signed-off-by: Matt Waddel <Matt.Waddel@freescale.com>
Signed-off-by: Greg Ungerer <gerg@uclinux.org>
diff --git a/drivers/net/fec.c b/drivers/net/fec.c
index 7e33c12..2769083 100644
--- a/drivers/net/fec.c
+++ b/drivers/net/fec.c
@@ -1698,7 +1698,7 @@
 	/*
 	 * Set MII speed to 2.5 MHz
 	 */
-	fep->phy_speed = ((((MCF_CLK / 2) / (2500000 / 10)) + 5) / 10) * 2;
+	fep->phy_speed = (MCF_CLK / 3) / (2500000 * 2 ) * 2;
 	fecp->fec_mii_speed = fep->phy_speed;
 
 	fec_restart(dev, 0);