Documentation: dt: socfpga: Add Stratix10 ECC Manager binding

Add the device tree bindings needed to support the Stratix10 ECC Manager
and SDRAM ECC.

Signed-off-by: Thor Thayer <thor.thayer@linux.intel.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: catalin.marinas@arm.com
Cc: devicetree@vger.kernel.org
Cc: dinguyen@kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-edac <linux-edac@vger.kernel.org>
Cc: mchehab@kernel.org
Cc: will.deacon@arm.com
Link: http://lkml.kernel.org/r/1524854238-19394-2-git-send-email-thor.thayer@linux.intel.com


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