kobjects: fix up improper use of the kobject name field

A number of different drivers incorrect access the kobject name field
directly.  This is not correct as the name might not be in the array.
Use the proper accessor function instead.

drivers/acpi/bus.c

@@ -194,7 +194,7 @@ int acpi_bus_set_power(acpi_handle handle, int state)
 
 	if (!device->flags.power_manageable) {
 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device `[%s]' is not power manageable\n",
-				device->dev.kobj.name));
+				kobject_name(&device->dev.kobj)));
 		return -ENODEV;
 	}
 	/*