EHCI: centralize controller initialization

This patch (as1564c) converts the EHCI platform drivers to use the
central ehci_setup() routine for generic controller initialization
rather than each having its own idiosyncratic approach.

The major point of difficulty lies in ehci-pci's many vendor- and
device-specific workarounds.  Some of them have to be applied before
calling ehci_setup() and some after, which necessitates a fair amount
of code motion.  The other platform drivers require much smaller
changes.

One point not addressed by the patch is whether ports should be
powered on or off following initialization.  The different drivers
appear to handle this pretty much at random.  In fact it shouldn't
matter, because the hub driver turns on power to all ports when it
binds to the root hub.  Straightening that out will be left for
another day.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>