USB: Handle DFU requests by USBD.c to keep application callback

e.g. in CCID mode we need to treat class-specific control requests,
and we want to do this in a way how the CCID code doesn't need to
understand about DFU.

firmware/atmel_softpack_libraries/usb/device/dfu/dfu_runtime.c

@@ -141,7 +141,7 @@ void USBDFU_Runtime_RequestHandler(const USBGenericRequest *request)
 	if (USBGenericRequest_GetType(request) != USBGenericRequest_CLASS ||
 	    USBGenericRequest_GetRecipient(request) != USBGenericRequest_INTERFACE) {
 		TRACE_DEBUG("std_ho_usbd ");
-		USBDDriver_RequestHandler(usbdDriver, request);
+		USBDCallbacks_RequestReceived(request);
 		return;
 	}
 
@@ -216,9 +216,3 @@ void DFURT_SwitchToDFU(void)
 	 * ResetVector of the bootloader */
 	NVIC_SystemReset();
 }
-
-void USBDCallbacks_RequestReceived(const USBGenericRequest *request)
-{
-	/* FIXME: integration with CCID control point reqeusts */
-	USBDFU_Runtime_RequestHandler(request);
-}