PCI: Inline and remove pcibios_update_irq()

pcibios_update_irq() was a weak function with only one trivial
implementation.  Inline it and remove the weak function.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

include/linux/pci.h

@@ -844,7 +844,6 @@ char *pcibios_setup(char *str);
 resource_size_t pcibios_align_resource(void *, const struct resource *,
 				resource_size_t,
 				resource_size_t);
-void pcibios_update_irq(struct pci_dev *, int irq);
 
 /* Weak but can be overriden by arch */
 void pci_fixup_cardbus(struct pci_bus *);