arm64: xilinx: dts: drop legacy property #stream-id-cells

Property #stream-id-cells is legacy leftover and isn't currently
documented nor used.

Signed-off-by: David Heidelberg <david@ixit.cz>
Link: https://lore.kernel.org/r/20211208184846.101166-1-david@ixit.cz


Signed-off-by: Michal Simek <michal.simek@xilinx.com>