ASoC: davinci-mcasp: Fix compilation error

Introduced by commit:
6afda7f5 ASoC: davinci-mcasp: Allow complete shutdown of McASP when not in use

I'm really sorry for this...

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Mark Brown <broonie@kernel.org>