When using level triggered IRQs, a new IRQ flag may already have been
set while the IRQ callback is executed. Hence, we cannot just toggle
the output, but rather should drive it low/high for a level trigger on
high/low.
Also test `gpio_ll_query_conf()` for the disconnected state as well.
Printing the newline after the state was printed is not optional.
This also moves the call to `gpio_ll_print_conf()` and `puts("")` to
a static function to safe enough ROM so that this still can be flashed
on `nucleo-l011k4`.
