Add the support for the am437x xhci usb host.
The xHCI host on AM437 is connected to a usb2 phy so need to
add support to enable those clocks.
Signed-off-by: Dan Murphy <dmurphy@ti.com>
Signed-off-by: Antoine Tenart <atenart@adeneo-embedded.com>
[trini: Fix warnings about vtp things in emif4.c, adapt AM43XX]
Signed-off-by: Tom Rini <trini@ti.com>