power: supply: bq256xx: drain usb_work before freeing the charger

In the Linux kernel, the following vulnerability has been resolved: power: supply: bq256xx: drain usb_work before freeing the charger The USB-PHY notifier queues usb_work, whose handler calls power_supply_changed(bq->charger). The reset devm action only unregisters the notifier and was registered before the power supplies, so devm frees bq->charger on unwind before the action runs; a usb_work still queued can then dereference it. Register the reset action after the power supplies, so it unregisters the notifiers and drains usb_work before the supplies are released. Initialize usb_work and obtain the PHY references before registering the notifiers, so the worker cannot run before the supplies exist. Found by static analysis.