ASoC: OMAP4: McPDM: Convert to hwmod/omap_device

In order to probe, and operate correctly, the OMAP McPDM driver needs to
be converted to use hwmod.
The device name has been changed to probe the driver.
Replace the clk_* with pm_runtime_* calls to manage the clocks correctly.
Missing request_mem_region/release_mem_region added.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Liam Girdwood <lrg@ti.com>