PCI: Add devm_pci_alloc_host_bridge() interface

Struct pci_host_bridge can be allocated by PCI host bridge drivers which
usually allocate and map memory through devm managed interfaces.

Add a devm version for the pci_alloc_host_bridge() interface to simplify
PCI host controller driver porting and simplify the driver failure paths.

Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: Arnd Bergmann <arnd@arndb.de>
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 9095b38..d39a66d 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -458,6 +458,8 @@ static inline struct pci_host_bridge *pci_host_bridge_from_priv(void *priv)
 }
 
 struct pci_host_bridge *pci_alloc_host_bridge(size_t priv);
+struct pci_host_bridge *devm_pci_alloc_host_bridge(struct device *dev,
+						   size_t priv);
 void pci_free_host_bridge(struct pci_host_bridge *bridge);
 int pci_register_host_bridge(struct pci_host_bridge *bridge);
 struct pci_host_bridge *pci_find_host_bridge(struct pci_bus *bus);