ASoC: omap: Use common DAI DMA data

Use the common DAI DMA data struct for omap, this allows us to use the common
helper function to configure the DMA slave config based on the DAI DMA data.

For omap-dmic and omap-mcpdm also move the DMA data from a global variable to
the driver state struct.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Acked-by: Jarkko Nikula <jarkko.nikula@bitmer.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>