powerpc/fman/memac: use default MDIO_HOLD value

Current driver uses a Maximum value for MDIO_HOLD when doing 10G MDIO
access, this is due to an errata A-006260 on T4 rev1.0 which is fixed
on rev2.0, so remove the maximum value to use the default value for rev2.0.
Signed-off-by: NShaohui Xie <Shaohui.Xie@freescale.com>

drivers/net/fm/memac_phy.c

@@ -29,10 +29,8 @@ int memac_mdio_write(struct mii_dev *bus, int port_addr, int dev_addr,
 		c45 = 0; /* clause 22 */
 		dev_addr = regnum & 0x1f;
 		clrbits_be32(&regs->mdio_stat, MDIO_STAT_ENC);
-	} else {
+	} else
 		setbits_be32(&regs->mdio_stat, MDIO_STAT_ENC);
-		setbits_be32(&regs->mdio_stat, MDIO_STAT_HOLD_15_CLK);
-	}
 
 	/* Wait till the bus is free */
 	while ((in_be32(&regs->mdio_stat)) & MDIO_STAT_BSY)
@@ -76,10 +74,8 @@ int memac_mdio_read(struct mii_dev *bus, int port_addr, int dev_addr,
 		c45 = 0; /* clause 22 */
 		dev_addr = regnum & 0x1f;
 		clrbits_be32(&regs->mdio_stat, MDIO_STAT_ENC);
-	} else {
+	} else
 		setbits_be32(&regs->mdio_stat, MDIO_STAT_ENC);
-		setbits_be32(&regs->mdio_stat, MDIO_STAT_HOLD_15_CLK);
-	}
 
 	/* Wait till the bus is free */
 	while ((in_be32(&regs->mdio_stat)) & MDIO_STAT_BSY)