ARM: PCI: add legacy IDE IRQ implementation

The IDE code used to specify the IDE IRQs for chipsets operating in
legacy mode.  This appears to no longer work, and this information must
be provided by the arch.  Do so.  This partially fixes CY82C693 (and
probably others) on Footbridge platforms.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/include/asm/pci.h b/arch/arm/include/asm/pci.h
index a98a2e1..680a83e 100644
--- a/arch/arm/include/asm/pci.h
+++ b/arch/arm/include/asm/pci.h
@@ -57,12 +57,9 @@
 extern int pci_mmap_page_range(struct pci_dev *dev, struct vm_area_struct *vma,
                                enum pci_mmap_state mmap_state, int write_combine);
 
-/*
- * Dummy implementation; always return 0.
- */
 static inline int pci_get_legacy_ide_irq(struct pci_dev *dev, int channel)
 {
-	return 0;
+	return channel ? 15 : 14;
 }
 
 #endif /* __KERNEL__ */