EDAC, layerscape: Add Layerscape EDAC support

Add DDR EDAC driver for ARM-based compatible controllers. Both
big-endian and little-endian are supported, as specified in device tree.

Signed-off-by: York Sun <york.sun@nxp.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-edac <linux-edac@vger.kernel.org>
Link: http://lkml.kernel.org/r/1471990465-27443-1-git-send-email-york.sun@nxp.com


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