Add pm runtime support for McBSP driver.
Reference to fclk is not removed because it is required when the
functional clock is switched from one source to another.
Signed-off-by: NKishon Vijay Abraham I <kishon@ti.com>
Cc: Paul Walmsley <paul@pwsan.com>
Acked-by: NPeter Ujfalusi <peter.ujfalusi@nokia.com>
Acked-by: NJarkko Nikula <jhnikula@gmail.com>
Acked-by: NMark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: NTony Lindgren <tony@atomide.com>