usb: chipidea: Add udc unregister for device removal
The host may assume that the usb device is still up and running after
booting if we do not deregister the udc here. I observed issues when the
linux kernel was using a usb gadget directly where the complete USB Hub
got disconnected through this.
This patch adds a proper USB disconnect for gadget devices.
Signed-off-by: Markus Pargmann <mpa@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>