DEVICE_POWER_STATE
PopLockGetDoDevicePowerState(
  IN  PDEVOBJ_EXTENSION Doe
  );

Routine Description:

    Function which returns the power state of the specified device.
    Unlike PopGetDoDevicePowerState, this routine also acquires and
    releases the appropriate spinlock.

Arguments:

    Doe - Supplies the devobj_extension of the device.

Return Value:

    DEVICE_POWER_STATE