USB: UHCI: add support for Intel's wakeup flags

This patch (as1396) adds code to uhci-hcd to support the
vendor-specific wakeup settings found in Intel's ICHx hardware.  A
couple of unnecessary memory barriers are removed.  And the root hub
isn't put back into the "suspended" state if power was lost during a
system sleep -- there's not much point in doing so because the root hub
will be resumed shortly.

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