tty: serial: meson: Use devm_ioremap_resource to get register mapped memory

Replace devm_request_mem_region and devm_ioremap with
devm_ioremap_resource to make the code cleaner.
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Yu Tu <yu.tu@amlogic.com>
Link: https://lore.kernel.org/r/20220225073922.3947-3-yu.tu@amlogic.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/tty/serial/meson_uart.c

@@ -720,15 +720,7 @@ static int meson_uart_probe(struct platform_device *pdev)
 	if (!port)
 		return -ENOMEM;
 
-	if (!devm_request_mem_region(&pdev->dev, res_mem->start,
-				     resource_size(res_mem),
-				     dev_name(&pdev->dev))) {
-		dev_err(&pdev->dev, "Memory region busy\n");
-		return -EBUSY;
-	}
-
-	port->membase = devm_ioremap(&pdev->dev, res_mem->start,
-				     resource_size(res_mem));
+	port->membase = devm_ioremap_resource(&pdev->dev, res_mem);
 	if (IS_ERR(port->membase))
 		return PTR_ERR(port->membase);