PCI/hotplug: ppc: correct a php_slot usage after free

In pnv_php_unregister_one(), pnv_php_put_slot() might kfree
php_slot structure. But there is pci_hp_deregister() after
that with php_slot reference.

This patch moves pnv_php_put_slot() to the end of function.
Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

drivers/pci/hotplug/pnv_php.c

@@ -919,8 +919,8 @@ static void pnv_php_unregister_one(struct device_node *dn)
 		return;
 
 	php_slot->state = PNV_PHP_STATE_OFFLINE;
-	pnv_php_put_slot(php_slot);
 	pci_hp_deregister(&php_slot->slot);
+	pnv_php_put_slot(php_slot);
 }
 
 static void pnv_php_unregister(struct device_node *dn)