ARC: dma [IOC]: mark DMA devices connected as dma-coherent

Mark DMA devices on AXS103 and HSDK boards connected through IOC
port as dma-coherent.

Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>