This patch collects various small updates related to root hubs, to shrink
later patches which build on them.
- For root hub suspend/resume support:
* Make the existing usb_hcd_resume_root_hub() routine respect pmcore
locking, exporting and using the dpm_runtime_resume() method.
* Add a new usb_hcd_suspend_root_hub() to pair with that routine.
(Essential to make OHCI autosuspend behave again...)
* HC_SUSPENDED by itself only refers to the root hub's downstream ports.
So let HCDs see root hub URBs unless the parent device is suspended.
- Remove an assertion we no longer need (and now, also don't want).
- Generic suspend/resume updates to work better with swsusp.
* Ignore the FREEZE vs SUSPEND distinction for hardware; trying to
use it breaks the swsusp snapshots it's supposed to help (sigh).
* On resume, mark devices as resumed right away, but then
do nothing else if the device is marked NOTATTACHED.
These changes shouldn't be very noticable by themselves.