arm: mvebu: Enable USB controllers on Armada 370/XP boards

This patch activates every USB port provided by each SoC.
Except for Armada XP Openblocks AX3-4 board,
where we enable only the first two USB ports
until we have more information on the third one usage.

Cc: Lior Amsalem <alior@marvell.com>
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Cc: Gregory CLEMENT <gregory.clement@free-electrons.com>
Tested-by: Nobuhiro Iwamatsu <iwamatsu@nigauri.org>
Tested-by: Florian Fainelli <florian@openwrt.org>
Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: Jason Cooper <jason@lakedaemon.net>