[ARM] Dove: add support for CM-A510 machine.

This patch adds support for CM-A510 machine

Signed-off-by: Konstantin Sinyuk <kostyas@compulab.co.il>
Signed-off-by: Mike Rapoport <mike@compulab.co.il>
Reviewed-by: Saeed Bishara <saeed@marvell.com>
Signed-off-by: Nicolas Pitre <nico@fluxnic.net>