PCI: Add device flag helper functions

Add helper functions to hide direct device flag operations:

    void pci_set_dev_assigned(struct pci_dev *dev);
    void pci_clear_dev_assigned(struct pci_dev *dev);
    bool pci_is_dev_assigned(struct pci_dev *dev);

Signed-off-by: Ethan Zhao <ethan.zhao@oracle.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

include/linux/pci.h

@@ -1839,4 +1839,17 @@ int pci_for_each_dma_alias(struct pci_dev *pdev,
  */
 struct pci_dev *pci_find_upstream_pcie_bridge(struct pci_dev *pdev);
 
+/* helper functions for operation of device flag */
+static inline void pci_set_dev_assigned(struct pci_dev *pdev)
+{
+	pdev->dev_flags |= PCI_DEV_FLAGS_ASSIGNED;
+}
+static inline void pci_clear_dev_assigned(struct pci_dev *pdev)
+{
+	pdev->dev_flags &= ~PCI_DEV_FLAGS_ASSIGNED;
+}
+static inline bool pci_is_dev_assigned(struct pci_dev *pdev)
+{
+	return (pdev->dev_flags & PCI_DEV_FLAGS_ASSIGNED) == PCI_DEV_FLAGS_ASSIGNED;
+}
 #endif /* LINUX_PCI_H */