arm64: zynqmp: Add dcc console for zynqmp

Add debug console to dtsi to be able to enable it in
board dts file.
Keep in your mind that every core has separate dcc port in case you want
to run SMP kernel.
DCC is very helpful communication channel for debugging.

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