Hard reset the power of this node.

def reboot(self):
        """Hard reset the power of this node.
           """
        if self.get_power_state() == LsPower.CONST_STATE_DOWN:
            self.set_power_state(LsPower.CONST_STATE_UP)
        else:
            self.set_power_state(LsPower.CONST_STATE_HARD_RESET_IMMEDIATE)