pci_disable_device — Disable PCI device after use
| void pci_disable_device ( | struct pci_dev * dev ); | 
Signal to the system that the PCI device is not in use by the system anymore. This only involves disabling PCI bus-mastering, if active.
   Note we don't actually disable the device until all callers of
   pci_enable_device have called pci_disable_device.