[PATCH] USB: ehci updates: CONFIG_PCI, integrated TT

[PATCH] USB: ehci updates:  CONFIG_PCI, integrated TT

Generalize the driver a bit:

 - PCI-specific handling is restricted to a small chunk of
   init code.  Non-PCI implementations are in the pipeline.

 - Merge support from ARC International (Craig Nadler) for
   their integrated root hub transaction translators (on PCI).
   Other implementations should be similar.