arm: mach-k3: j722s: Add QoS support for DSS

arm: mach-k3: j722s: Add QoS support for DSS

Enable Quality of Service (QoS) blocks for Display SubSystem (DSS), by
servicing the DSS - DDR traffic from the Real-Time (RT) queue. This is
done by setting the DSS DMA orderID to greater than 7.

The C7x and VPAC can overwhelm the DSS's access to the DDR because of
their higher frequency DDR accesses. This can cause flickering in
display with certain edgeAI models running parallely if the DSS traffic
is being serviced through non-RT queue.

Signed-off-by: Jayesh Choudhary <j-choudhary@ti.com>
Reviewed-by: Devarsh Thakkar <devarsht@ti.com>