linux-wandboard

usb: musb: gadget: do not poke with gadget's list_head

struct usb_request's list_head is supposed to be
used only by gadget drivers, but musb is abusing
that. Give struct musb_request its own list_head
and prevent musb from poking into other driver's
business.

Signed-off-by: Felipe Balbi <balbi@ti.com>