ASoC: omap-mcbsp: Convert to use the sdma-pcm instead of omap-pcm

Use the new platform driver.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Acked-by: Jarkko Nikula <jarkko.nikula@bitmer.com>
Signed-off-by: Mark Brown <broonie@kernel.org>