This fixes some bugs in EHCI suspend/resume that joined us over the past
few releases (as usbcore, PCI, pmcore, and other components evolved):
- Removes suspend and resume recursion from the EHCI driver, getting
rid of the USB_SUSPEND special casing.
- Updates the wakeup mechanism to work again; there's a newish usbcore
call it needs to use.
- Provide simpler tests for "do we need to restart from scratch", to
address another case where PCI Vaux was lost. (In this case it was
restoring a swsusp snapshot, but there could be others.)
Un-exports a symbol that was temporarily exported.
A notable change from previous version is that this doesn't move
the spinlock init, so there's still a resume/reinit path bug.