serial: arc_uart: fix of_iomap leak in arc_serial_probe

Smatch reports:

drivers/tty/serial/arc_uart.c:631 arc_serial_probe() warn:
'port->membase' from of_iomap() not released on lines: 631.

In arc_serial_probe(), if uart_add_one_port() fails,
port->membase is not released, which would cause a resource leak.

To fix this, I replace of_iomap with devm_platform_ioremap_resource.

Fixes: 8dbe1d5 ("serial/arc: inline the probe helper")
Signed-off-by: Ke Zhang <m202171830@hust.edu.cn>
Reviewed-by: Dongliang Mu <dzm91@hust.edu.cn>
Link: https://lore.kernel.org/r/20230428031636.44642-1-m202171830@hust.edu.cn
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Author: souikk

drivers/tty/serial/arc_uart.c

@@ -606,10 +606,11 @@ static int arc_serial_probe(struct platform_device *pdev)
 	}
 	uart->baud = val;
 
-	port->membase = of_iomap(np, 0);
-	if (!port->membase)
+	port->membase = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(port->membase)) {
 		/* No point of dev_err since UART itself is hosed here */
-		return -ENXIO;
+		return PTR_ERR(port->membase);
+	}
 
 	port->irq = irq_of_parse_and_map(np, 0);