ARM: mvebu: add gpio fan support to Armada 370 RD

The Armada 370 RD platform has a GPIO-controlled fan on MPP8, so this
commit adds the relevant hardware description to Armada 370 RD Device
Tree.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Acked-by: Andrew Lunn <andrew@lunn.ch>
Link: https://lkml.kernel.org/r/1410429419-29820-2-git-send-email-thomas.petazzoni@free-electrons.com


Signed-off-by: Jason Cooper <jason@lakedaemon.net>