USB: UHCI: Support non-PCI host controllers

This patch is part of a series that extend the UHCI HCD to support
non-PCI host controllers.

This patch also extends the uhci_{read,write}* functions to allow accesses
to registers not mapped into PCI I/O space. This extension also includes
the addition of a void __iomem pointer to the uhci structure.

A new Kconfig option is added to signal that the system has a non-PCI HC.
If this Kconfig option is set, uhci-hcd.c will include generic reset functions
for systems that do not make use of keyboard and mouse legacy support. PCI
controllers will still always use the reset functions from pci-quirks

This patch is followed by a patch that adds bus glue for the first non-PCI
UHCI HC.

Signed-off-by: Jan Andersson <jan@gaisler.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>