Provide the top level ASoC core functions for indicating whether
a given register is readable or writable.
Signed-off-by: NDimitris Papastamos <dp@opensource.wolfsonmicro.com>
Acked-by: NLiam Girdwood <lrg@ti.com>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>