as prepare callback for dma is acctually access ssc register
which better done in dai driver, so move it to dai prepare
callback function
Signed-off-by: NBo Shen <voice.shen@atmel.com>
Reviewed-by: NLars-Peter Clausen <lars@metafoo.de>
Signed-off-by: NMark Brown <broonie@linaro.org>