Make the dma-channel-mask to be usable for controllers with more than 32
channels.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20191025073056.25450-2-peter.ujfalusi@ti.com


Signed-off-by: Vinod Koul <vkoul@kernel.org>