ARM: mvebu: enable the SATA interface on Armada 375 DB

The Armada 375 SoC has a dual-port SATA interface, which is exposed on
the Armada 375 DB board. This commit therefore enables this interface
on the Armada 375 DB board.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Acked-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Link: https://lkml.kernel.org/r/1397806908-7550-3-git-send-email-thomas.petazzoni@free-electrons.com
Signed-off-by: Jason Cooper <jason@lakedaemon.net>