usb: gadget: push all usb_composite_driver structs into __refdata

As it turns out, Sam's comment was better than I initially assumed. This
patch pushes as struct usb_composite_driver data structures into
__refdata section to avoid a section missmatch report from modpost
because the ->bind() can be marked __init. The only downside is that
modpost does not check between ->bind() and other member. However, it is
temporary.

Cc: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Michal Nazarewicz <mina86@mina86.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Felipe Balbi <balbi@ti.com>

drivers/usb/gadget/dbgp.c

@@ -402,7 +402,7 @@ fail:
 	return err;
 }
 
-static struct usb_gadget_driver dbgp_driver = {
+static __refdata struct usb_gadget_driver dbgp_driver = {
 	.function = "dbgp",
 	.max_speed = USB_SPEED_HIGH,
 	.unbind = dbgp_unbind,