ASoC: omap-mcbsp: Remove cpu_is_omap* checks from the code

We can use the has_ccr flag to replace the cpu_is_omap* checks.
This provides future proof implementation and we do not need to update the
code if new OMAP revision starts to use the McBSP driver.

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