ide: hook ACPI _PSx method to IDE power on/off

ACPI spec defines the sequence of IDE power on/off:
Powering down:
	Call _GTM.
	Power down drive (calls _PS3 method and turns off power planes).
Powering up:
	Power up drive (calls _PS0 method if present and turns on power planes).
	Call _STM passing info from _GTM (possibly modified), with ID data from
	each drive.
	Initialize the channel.
	May modify the results of _GTF.
	For each drive:
		Call _GTF.
		Execute task file (possibly modified).
This patch adds the missed _PS0/_PS3 methods call.

Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Acked-by: Len Brown <len.brown@intel.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

drivers/acpi/bus.c

@@ -262,10 +262,12 @@ int acpi_bus_set_power(acpi_handle handle, int state)
 		printk(KERN_WARNING PREFIX
 			      "Transitioning device [%s] to D%d\n",
 			      device->pnp.bus_id, state);
-	else
+	else {
+		device->power.state = state;
 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 				  "Device [%s] transitioned to D%d\n",
 				  device->pnp.bus_id, state));
+	}
 
 	return result;
 }