USB: UHCI: Add support for big endian descriptors

This patch adds support for universal host controllers that use
big endian descriptors. Support for BE descriptors requires a non-PCI
host controller. For kernels with PCI-only UHCI there should be no
change in behaviour.

This patch tries to replicate the technique used to support BE descriptors
in the EHCI HCD. Parts added to uhci-hcd.h are basically copy'n'paste from
ehci.h.

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>