Merge pull request #3502 from roma-jam-lab/dbg/nested_hubs_address_empty_warning

add(usbh.c): LOG1 debug message when no address available for hub

src/host/usbh.c

@@ -1841,6 +1841,12 @@ static uint8_t enum_get_new_address(bool is_hub) {
     }
   }
 
+#if CFG_TUH_HUB
+  if ( is_hub ) {
+    TU_LOG1("All addresses are occupied, try to increase CFG_TUH_HUB value.\r\n");
+  }
+#endif // CFG_TUH_HUB
+
   return 0; // invalid address
 }