usb: add support for hardware handled SET ADDR/CONFIG

Some USB controllers like the one of the Rockchip 27xx handle some
requests in pure hardware. This is especially a problem for two
of them:
- SET ADDR which is used by our core to track the DEFAULT/ADDRESS
  state and is required for the drivers to work properly
- SET CONFIG which is used by our core to initialise the drivers
  by calling init_connection()
In these cases we need a way to notify the core that such requests
happened.
We do this by exporting two functions which directly notify the
core about these requests and perform the necessary init steps
required without doing the actual USB transfers. Special care is
needed because these functions could be called from an interrupt
handler. For this reason we still use the usb_queue and introduce
new IDs so that they are processed in order and safely.

No functional change is intended, both in the usbstack and on
targets without such quirks.

Change-Id: Ie42feffd4584e88bf37cff018b627f333dca1140

firmware/export/usb_core.h

@@ -51,6 +51,10 @@ void usb_core_enable_driver(int driver,bool enabled);
 bool usb_core_driver_enabled(int driver);
 void usb_core_handle_transfer_completion(
         struct usb_transfer_completion_event_data* event);
+void usb_core_handle_notify(long id, intptr_t data);
+/* For controllers which handle SET ADDR and/or SET CONFIG in hardware */
+void usb_core_notify_set_address(uint8_t addr);
+void usb_core_notify_set_config(uint8_t config);
 
 int usb_core_request_endpoint(int type, int dir,struct usb_class_driver* drv);
 void usb_core_release_endpoint(int dir);