pinctrl: meson: Drop pinctrl_unregister for devm_ registered device

It's not necessary to unregister pin controller device registered
with devm_pinctrl_register() and using pinctrl_unregister() leads
to a double free.

This is detected by Coccinelle semantic patch.

Fixes: e649f7ec8c5f ("pinctrl: meson: Use devm_pinctrl_register() for pinctrl registration")
Signed-off-by: Wei Yongjun <weiyj.lk@gmail.com>
Reviewed-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Acked-by: Kevin Hilman <khilman@baylibre.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/pinctrl/meson/pinctrl-meson.c

@@ -727,13 +727,7 @@ static int meson_pinctrl_probe(struct platform_device *pdev)
 		return PTR_ERR(pc->pcdev);
 	}
 
-	ret = meson_gpiolib_register(pc);
-	if (ret) {
-		pinctrl_unregister(pc->pcdev);
-		return ret;
-	}
-
-	return 0;
+	return meson_gpiolib_register(pc);
 }
 
 static struct platform_driver meson_pinctrl_driver = {