* No need for sme_refresh callback; GPE handler will tell us when the
device status changed (otherwise we can refresh data up to once a second,
and that can take time!)
* Since sme_refresh callback is gone, mutex is no longer required to
synchronize GPE handlers and refresh thread, so nuke it.
* Don't do any more work in GPE handler than required; use AcpiOsExecute
to clear battery status/information in the sysmon_task_queue along with
the refresh.
With these changes running GNOME's battstat-applet-2 no longer causes
my mouse to stutter once a second, and significantly reduces its CPU usage.
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