remove the folder where zio lists all the available triggers, buffers
and devices. Now you can find devices at /sys/bus/zio/devices/, and
retrive the list of the available triggers and buffers from:
/sys/bus/zio/available_buffers
/sys/bus/zio/available_triggers

Signed-off-by: Federico Vaga <federico.vaga@gmail.com>
Acked-by: Alessandro Rubini <rubini@gnudd.com>