USB: gadget: udc: renesas_usb3: no need to check return value of debugfs_create functions

When calling debugfs functions, there is no need to ever check the
return value.  The function can work or not, but the code logic should
never do something different based on this.

Cc: Felipe Balbi <balbi@kernel.org>
Cc: Simon Horman <horms+renesas@verge.net.au>
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: NYoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/gadget/udc/renesas_usb3.c

@@ -2391,22 +2391,10 @@ static const struct file_operations renesas_usb3_b_device_fops = {
 static void renesas_usb3_debugfs_init(struct renesas_usb3 *usb3,
 				      struct device *dev)
 {
-	struct dentry *root, *file;
+	usb3->dentry = debugfs_create_dir(dev_name(dev), NULL);
 
-	root = debugfs_create_dir(dev_name(dev), NULL);
-	if (IS_ERR_OR_NULL(root)) {
-		dev_info(dev, "%s: Can't create the root\n", __func__);
-		return;
-	}
-
-	file = debugfs_create_file("b_device", 0644, root, usb3,
-				   &renesas_usb3_b_device_fops);
-	if (!file) {
-		dev_info(dev, "%s: Can't create debugfs mode\n", __func__);
-		debugfs_remove_recursive(root);
-	} else {
-		usb3->dentry = root;
-	}
+	debugfs_create_file("b_device", 0644, usb3->dentry, usb3,
+			    &renesas_usb3_b_device_fops);
 }
 
 /*------- platform_driver ------------------------------------------------*/