MIPS: xilfpga: Add DT node for AXI emaclite

The xilfpga platform has a Xilinx AXI emaclite block.

Add the DT node to use it.

Signed-off-by: Zubair Lutfullah Kakakhel <Zubair.Kakakhel@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14596/


Signed-off-by: Ralf Baechle <ralf@linux-mips.org>