usb: gadget: pxa27x_udc: convert to udc_start/udc_stop

Mechanical change making use of the new (can we
still call it new ?) interface for registering
UDC drivers.

Signed-off-by: Felipe Balbi <balbi@ti.com>
diff --git a/drivers/usb/gadget/pxa27x_udc.h b/drivers/usb/gadget/pxa27x_udc.h
index 79d81a4..28f2b53 100644
--- a/drivers/usb/gadget/pxa27x_udc.h
+++ b/drivers/usb/gadget/pxa27x_udc.h
@@ -473,6 +473,7 @@
 	struct dentry				*debugfs_eps;
 #endif
 };
+#define to_pxa(g)	(container_of((g), struct pxa_udc, gadget))
 
 static inline struct pxa_udc *to_gadget_udc(struct usb_gadget *gadget)
 {