ASoC: pcm3168a: Allow all channels in case of parallel DIN/DOUT setup

If multi DIN/DOUT mode is selected (tdm_slots == 2) then configure the
channel constraint to allow all channels.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Link: https://lore.kernel.org/r/20190725083321.6776-1-peter.ujfalusi@ti.com


Signed-off-by: Mark Brown <broonie@kernel.org>