Function kernel::daemons::shells::io_poll

async fn io_poll(
    style: PollStyle,
    keyboard: &mut KeyClient,
    rline: &mut RingLine<16, 46>,
    tid_io: &BidiHandle,
)

Poll the IO interfaces until something interesting happens.

If called with OneShot style: return as soon as SOMETHING productive occurs.

If called with Forever style: Never return, requires the use of an outer timeout.