STM32 OTG FS Hose and others: Remove some warnings

configs/stm32f4discovery/src/stm32_usb.c

@@ -109,6 +109,7 @@ static int usbhost_waiter(int argc, char *argv[])
 
       ret = CONN_WAIT(g_usbconn, &connected);
       DEBUGASSERT(ret == OK);
+      UNUSED(ret);
 
       connected = !connected;
       uvdbg("%s\n", connected ? "connected" : "disconnected");
@@ -289,6 +290,3 @@ void stm32_usbsuspend(FAR struct usbdev_s *dev, bool resume)
 #endif
 
 #endif /* CONFIG_STM32_OTGFS */
-
-
-