Cleanups

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Allow to restart the FIQ once it has failed

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Implement underruns detection in the FIQ handler

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Fix size computation

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Update the sample client to generate two frequencies and handle errors

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>