ASoC: Fix SmartQ compilation

This makes the SmartQ sound driver compile again with recent ASoC changes.

Signed-off-by: Maurus Cuelenaere <mcuelenaere@gmail.com>
Acked-by: Liam Girdwood <lrg@slimlogic.co.uk>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>