PCI/AER: Move aer_irq() declaration to portdrv.h

The aer_irq() declaration is the only thing needed by aer_inject.c.  Move
it to portdrv.h so we eventually get rid of aerdrv.h completely.  No
functional change intended.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Keith Busch <keith.busch@intel.com>

drivers/pci/pcie/portdrv.h

@@ -121,6 +121,10 @@ static inline int pcie_aer_get_firmware_first(struct pci_dev *pci_dev)
 }
 #endif
 
+#ifdef CONFIG_PCIEAER
+irqreturn_t aer_irq(int irq, void *context);
+#endif
+
 struct pcie_port_service_driver *pcie_port_find_service(struct pci_dev *dev,
 							u32 service);
 struct device *pcie_port_find_device(struct pci_dev *dev, u32 service);