Test misc races when adding/releasing devices
v2.: use one roundtrip after releasing devices
add touch support
v3.: remove useless checks
add few comments
repeat tests 30 times instead of 100 times
(it took too long, 30 is enough)
Signed-off-by: Marek Chalupa <mchqwerty@gmail.com>
Reviewed-by: Pekka Paalanen <pekka.paalanen@collabora.co.uk>