pick up "usb: dwc2: Avoid leaving the error_debugfs label unused"

Hi Sasha-

To fix an unused-label warning, please pick up this mainline commit:

190bb01b72d2 ("usb: dwc2: Avoid leaving the error_debugfs label unused")

in these stable branches:

linux-5.8.y linux-5.9.y

For reference, the warning was introduced by the stable backports of [mainline] e1c08cf23172 ("usb: dwc2: Add missing cleanups when usb_add_gadget_udc() fails")

Thanks!

-Kamal