parisc: Directly call machine_power_off() in power button driver

Signed-off-by: Helge Deller <deller@gmx.de>
Tested-by: Matt Turner <mattst88@gmail.com>

drivers/parisc/power.c

@@ -95,8 +95,7 @@ static void process_shutdown(void)
 		/* send kill signal */
 		if (kill_cad_pid(SIGINT, 1)) {
 			/* just in case killing init process failed */
-			if (pm_power_off)
-				pm_power_off();
+			machine_power_off();
 		}
 	}
 }