a lot of thread housekeeping. Switch them off when not needed / disabled.

src/input/cardKbI2cImpl.cpp

@@ -13,6 +13,8 @@ void CardKbI2cImpl::init()
     if (cardkb_found != CARDKB_ADDR)
     {
         // Input device is not detected.
+        setInterval(INT32_MAX);
+        enabled = false;
         return;
     }