Initialise the adapter status to an invalid state, so that the initial check

of the adapter object will always result in a change event.

This fixes the problem where a laptop booted without an AC adapter ran
at 100% CPU speed by default.

Submitted by:	"Christopher N . Harrell" <cnh@netvmg.com>

sys/dev/acpica/acpi_acad.c

@@ -158,6 +158,7 @@ acpi_acad_attach(device_t dev)
 	}
 
 	/* Get initial status after whole system is up. */
+	sc->status = -1;
 	AcpiOsQueueForExecution(OSD_PRIORITY_LO, acpi_acad_get_status, dev);
 
 	return(0);