serial: stm32: clean probe and remove port deinit

Clean probe and remove port deinit by moving clk_disable_unprepare in a
new dedicated deinit_port function.
Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com>
Signed-off-by: Etienne Carriere <etienne.carriere@foss.st.com>
Link: https://lore.kernel.org/r/20210106162203.28854-8-erwan.leray@foss.st.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/tty/serial/stm32-usart.c

@@ -970,6 +970,11 @@ static const struct uart_ops stm32_uart_ops = {
 	.verify_port	= stm32_usart_verify_port,
 };
 
+static void stm32_usart_deinit_port(struct stm32_port *stm32port)
+{
+	clk_disable_unprepare(stm32port->clk);
+}
+
 static int stm32_usart_init_port(struct stm32_port *stm32port,
 				 struct platform_device *pdev)
 {
@@ -1279,7 +1284,7 @@ static int stm32_usart_serial_probe(struct platform_device *pdev)
 		device_init_wakeup(&pdev->dev, false);
 
 err_uninit:
-	clk_disable_unprepare(stm32port->clk);
+	stm32_usart_deinit_port(stm32port);
 
 	return ret;
 }
@@ -1318,7 +1323,7 @@ static int stm32_usart_serial_remove(struct platform_device *pdev)
 		device_init_wakeup(&pdev->dev, false);
 	}
 
-	clk_disable_unprepare(stm32_port->clk);
+	stm32_usart_deinit_port(stm32_port);
 
 	err = uart_remove_one_port(&stm32_usart_driver, port);