ARM: mvebu: add PHY support to the dts for the USB controllers on Armada 375

Now that the USB cluster node has been added, use it as a PHY provider
for the USB controller linked to it: the first EHCI and the xHCI.

Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Link: https://lkml.kernel.org/r/1415879269-29711-7-git-send-email-gregory.clement@free-electrons.com


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