dma: dw-axi-dmac: support per channel interrupt

Hardware might not support a single combined interrupt that covers all
channels. In that case we have to deal with interrupt per channel. Add
support for that configuration.

Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Link: https://lore.kernel.org/r/ebab52e886ef1adc3c40e636aeb1ba3adfe2e578.1711453387.git.baruchs-c@neureality.ai
Signed-off-by: Vinod Koul <vkoul@kernel.org>