serial: sccnxp: Use devm_clk_get_enabled() helper

The devm_clk_get_enabled() helper:
   - calls devm_clk_get()
   - calls clk_prepare_enable() and registers what is needed in order to
     call clk_disable_unprepare() when needed, as a managed resource.

This simplifies the code.
This also avoids some other warnings/issues. (see [1])

[1]: https://lore.kernel.org/all/20221118233101.never.215-kees@kernel.org/Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: https://lore.kernel.org/r/735a807c2df835aa436dcbc76b374f983f89a9af.1672419577.git.christophe.jaillet@wanadoo.frSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/tty/serial/sccnxp.c

@@ -913,23 +913,13 @@ static int sccnxp_probe(struct platform_device *pdev)
 	} else if (PTR_ERR(s->regulator) == -EPROBE_DEFER)
 		return -EPROBE_DEFER;
 
-	clk = devm_clk_get(&pdev->dev, NULL);
+	clk = devm_clk_get_enabled(&pdev->dev, NULL);
 	if (IS_ERR(clk)) {
 		ret = PTR_ERR(clk);
 		if (ret == -EPROBE_DEFER)
 			goto err_out;
 		uartclk = 0;
 	} else {
-		ret = clk_prepare_enable(clk);
-		if (ret)
-			goto err_out;
-
-		ret = devm_add_action_or_reset(&pdev->dev,
-				(void(*)(void *))clk_disable_unprepare,
-				clk);
-		if (ret)
-			goto err_out;
-
 		uartclk = clk_get_rate(clk);
 	}