net: mscc: ocelot: remove redundant dev_err call in vsc9959_mdio_bus_alloc()

There is a error message within devm_ioremap_resource
already, so remove the dev_err call to avoid redundant
error message.
Reported-by: NHulk Robot <hulkci@huawei.com>
Signed-off-by: NGuobin Huang <huangguobin4@huawei.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/dsa/ocelot/felix_vsc9959.c

@@ -1057,10 +1057,8 @@ static int vsc9959_mdio_bus_alloc(struct ocelot *ocelot)
 	res.end += felix->imdio_base;
 
 	imdio_regs = devm_ioremap_resource(dev, &res);
-	if (IS_ERR(imdio_regs)) {
-		dev_err(dev, "failed to map internal MDIO registers\n");
+	if (IS_ERR(imdio_regs))
 		return PTR_ERR(imdio_regs);
-	}
 
 	hw = enetc_hw_alloc(dev, imdio_regs);
 	if (IS_ERR(hw)) {