usb: renesas_usbhs: gadget: usbhsg_ep_disable() care pipe settings

Current usbhsg_ep_disable() didn't care
uep->pipe and pipe->mod_private variable which is used on usbhsg_ep_enable().
It breaks renesas_usbhs gadget when resume.
This patch fixes it.

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>