PCI: ibmphp_core.c: fix warning due to missing module_exit()

drivers/pci/hotplug/ibmphp_core.c:1414: warning: `ibmphp_exit' defined but not used
Signed-off-by: NZhenwen Xu <helight.xu@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

drivers/pci/hotplug/ibmphp_core.c

@@ -1419,3 +1419,4 @@ static void __exit ibmphp_exit(void)
 }
 
 module_init(ibmphp_init);
+module_exit(ibmphp_exit);