OMAP: McBSP: APIs to pass DMA params from McBSP driver to client drivers

After McBSP driver is hwmod adapted, the information about the hw would be
obtained from the hwmod database by the mcbsp driver. Since DMA programming is
handled by the client driver, APIs are provided to pass the DMA channel number
and base address of data register required by the client driver for DMA
programming.

Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Charulatha V <charu@ti.com>
Acked-by: Peter Ujfalusi <peter.ujfalusi@nokia.com>
Acked-by: Jarkko Nikula <jhnikula@gmail.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>