arm64: dts: ti: k3-j7200: add DMA support

Add the ringacc and udmap nodes for Main and MCU NAVSS.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Nishanth Menon <nm@ti.com>
Reviewed-by: Suman Anna <s-anna@ti.com>
Link: https://lore.kernel.org/r/20200923220938.30788-2-grygorii.strashko@ti.com