USB: phy: tahvo: convert platform driver to use dev_groups

Platform drivers now have the option to have the platform core create
and remove any needed sysfs attribute files. So take advantage of that
and do not register "by hand" any sysfs files.

Cc: Felipe Balbi <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

drivers/usb/phy/phy-tahvo.c

···
 }
 static DEVICE_ATTR_RW(otg_mode);
 
-static struct attribute *tahvo_attributes[] = {
+static struct attribute *tahvo_attrs[] = {
 	&dev_attr_vbus.attr,
 	&dev_attr_otg_mode.attr,
 	NULL
 };
-
-static const struct attribute_group tahvo_attr_group = {
-	.attrs = tahvo_attributes,
-};
+ATTRIBUTE_GROUPS(tahvo);
 
 static int tahvo_usb_probe(struct platform_device *pdev)
 {
···
 		goto err_remove_phy;
 	}
 
-	/* Attributes */
-	ret = sysfs_create_group(&pdev->dev.kobj, &tahvo_attr_group);
-	if (ret) {
-		dev_err(&pdev->dev, "cannot create sysfs group: %d\n", ret);
-		goto err_free_irq;
-	}
-
 	return 0;
 
-err_free_irq:
-	free_irq(tu->irq, tu);
 err_remove_phy:
 	usb_remove_phy(&tu->phy);
 err_disable_clk:
···
 {
 	struct tahvo_usb *tu = platform_get_drvdata(pdev);
 
-	sysfs_remove_group(&pdev->dev.kobj, &tahvo_attr_group);
 	free_irq(tu->irq, tu);
 	usb_remove_phy(&tu->phy);
 	if (!IS_ERR(tu->ick))
···
 	.remove		= tahvo_usb_remove,
 	.driver		= {
 		.name	= "tahvo-usb",
+		.dev_groups = tahvo_groups,
 	},
 };
 module_platform_driver(tahvo_usb_driver);