ohci-platform: Add support for devicetree instantiation

Add support for ohci-platform instantiation from devicetree, including
optionally getting clks and a phy from devicetree, and enabling / disabling
those on power_on / off.

This should allow using ohci-platform from devicetree in various cases.
Specifically after this commit it can be used for the ohci controller found
on Allwinner sunxi SoCs.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
ehci-platform: Add support for clks and phy passed through devicetree

Currently ehci-platform is only used in combination with devicetree when used
with some Via socs. By extending it to (optionally) get clks and a phy from
devicetree, and enabling / disabling those on power_on / off, it can be used
more generically. Specifically after this commit it can be used for the
ehci controller on Allwinner sunxi SoCs.

Since ehci-platform is intended to handle any generic enough non pci ehci
device, add a "usb-ehci" compatibility string.

There already is a usb-ehci device-tree bindings document, update this
with clks and phy bindings info.

Although actually quite generic so far the via,vt8500 compatibilty string
had its own bindings document. Somehow we even ended up with 2 of them. Since
these provide no extra information over the generic usb-ehci documentation,
this patch removes them.

The ehci-ppc-of.c driver also claims the usb-ehci compatibility string,
even though it mostly is ibm,usb-ehci-440epx specific. ehci-platform.c is
not needed on ppc platforms, so add a !PPC_OF dependency to it to avoid
2 drivers claiming the same compatibility string getting build on ppc.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
ARM: sunxi: Add driver for sunxi usb phy

The Allwinner A1x / A2x SoCs have 2 or 3 usb phys which are all accessed
through a single set of registers. Besides this there are also some other
phy related bits which need poking, which are per phy, but shared between the
ohci and ehci controllers, so these are also controlled from this new phy
driver.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>