phy: samsung_usb2: Fixup samsung_usb2_phy_power_on/off paths

Ensure we have balanced clk_prepare_enable/clk_disable_unprepare calls if
.power_on or .power_off callbacks return error.

Signed-off-by: Axel Lin <[e-mail]>
Signed-off-by: Kishon Vijay Abraham I <[e-mail]>

drivers/phy/phy-samsung-usb2.c

···
 		spin_lock(&drv->lock);
 		ret = inst->cfg->power_on(inst);
 		spin_unlock(&drv->lock);
+		if (ret)
+			goto err_power_on;
 	}
 
 	return 0;
 
+err_power_on:
+	clk_disable_unprepare(drv->ref_clk);
 err_instance_clk:
 	clk_disable_unprepare(drv->clk);
 err_main_clk:
···
 {
 	struct samsung_usb2_phy_instance *inst = phy_get_drvdata(phy);
 	struct samsung_usb2_phy_driver *drv = inst->drv;
-	int ret = 0;
+	int ret;
 
 	dev_dbg(drv->dev, "Request to power_off \"%s\" usb phy\n",
 		inst->cfg->label);
···
 		spin_lock(&drv->lock);
 		ret = inst->cfg->power_off(inst);
 		spin_unlock(&drv->lock);
+		if (ret)
+			return ret;
 	}
 	clk_disable_unprepare(drv->ref_clk);
 	clk_disable_unprepare(drv->clk);
-	return ret;
+	return 0;
 }
 
 static struct phy_ops samsung_usb2_phy_ops = {