PCI: add pci_stop_bus_device

This patch adds pci_stop_bus_device() which stops a PCI device (detach
the driver, remove from the global list and so on) and any children.
This is needed for ACPI based PCI-to-PCI bridge hot-remove, and it will
be also needed for ACPI based PCI root bridge hot-remove.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: MUNEDA Takahiro <muneda.takahiro@jp.fujitsu.com>
Signed-off-by: Satoru Takeuchi <takeuchi_satoru@jp.fujitsu.com>
Signed-off-by: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/include/linux/pci.h b/include/linux/pci.h
index 549d841..5c3a417 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -441,6 +441,7 @@
 extern void pci_dev_put(struct pci_dev *dev);
 extern void pci_remove_bus(struct pci_bus *b);
 extern void pci_remove_bus_device(struct pci_dev *dev);
+extern void pci_stop_bus_device(struct pci_dev *dev);
 void pci_setup_cardbus(struct pci_bus *bus);
 
 /* Generic PCI functions exported to card drivers */