Documentation: dt: socfpga: Add Arria10 Ethernet binding

Add the device tree bindings needed to support the Altera Ethernet FIFO
buffers on the Arria10 chip.

Signed-off-by: Thor Thayer <tthayer@opensource.altera.com>
Acked-by: Rob Herring <robh@kernel.org>
Cc: devicetree@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-edac <linux-edac@vger.kernel.org>
Link: http://lkml.kernel.org/r/1466603939-7526-6-git-send-email-tthayer@opensource.altera.com


Signed-off-by: Borislav Petkov <bp@suse.de>