usb: gadget: legacy: gmidi: remove useless cast for driver.name

usb_composite_driver name is const char pointer, so it not useful to cast
longname (which is already const char).
Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
Link: https://lore.kernel.org/r/1582054383-35760-2-git-send-email-clabbe@baylibre.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/gadget/legacy/gmidi.c

@@ -174,7 +174,7 @@ static int midi_bind(struct usb_composite_dev *cdev)
 }
 
 static struct usb_composite_driver midi_driver = {
-	.name		= (char *) longname,
+	.name		= longname,
 	.dev		= &device_desc,
 	.strings	= dev_strings,
 	.max_speed	= USB_SPEED_HIGH,