This patch is mostly cleanup, but it all helps make PM_SUSPEND_DISK
start to behave better.


This exports the new usb_set_device_state() routine for the virtual root
hubs, and uses it in OHCI during resume after power-off to replace some
HC-private code doing almost the same thing.

Note that all HCDs will likely need the same kind of suspend-to-disk
support (though it's different when BIOS kicks in).  Some systems
even power-off during suspend-to-ram (to save extra power), which is
why OHCI already has this logic!

Related updates:

 - Use usb_set_device_state() immediately when an HC dies, making khubd
   handle disconnect processing instead of a workqueue.  So now drivers
   won't self-deadlock in this should-be-rare path, when disconnect()
   calls flush_scheduled_work().

 - Don't warn about "Unlink after no-IRQ" for the the root hub's status
   URB ... like when suspending an HCD that never enumerated a device.

 - Minor IRQ handler cleanup, including more accurate tracking of whether
   this driver ever returned IRQ_HANDLED (shared IRQs don't count).
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>