alpha: Add irongate_io to PCI bus resources

Fixes a NULL pointer dereference at boot on UP1500.

Cc: stable@vger.kernel.org
Reviewed-and-Tested-by: Matt Turner <mattst88@gmail.com>
Signed-off-by: Jay Estabrook <jay.estabrook@gmail.com>
Signed-off-by: Matt Turner <mattst88@gmail.com>
Signed-off-by: Michael Cree <mcree@orcon.net.nz>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/arch/alpha/kernel/sys_nautilus.c b/arch/alpha/kernel/sys_nautilus.c
index 4d4c046..1383f86 100644
--- a/arch/alpha/kernel/sys_nautilus.c
+++ b/arch/alpha/kernel/sys_nautilus.c
@@ -188,6 +188,10 @@
 extern void free_reserved_mem(void *, void *);
 extern void pcibios_claim_one_bus(struct pci_bus *);
 
+static struct resource irongate_io = {
+	.name	= "Irongate PCI IO",
+	.flags	= IORESOURCE_IO,
+};
 static struct resource irongate_mem = {
 	.name	= "Irongate PCI MEM",
 	.flags	= IORESOURCE_MEM,
@@ -209,6 +213,7 @@
 
 	irongate = pci_get_bus_and_slot(0, 0);
 	bus->self = irongate;
+	bus->resource[0] = &irongate_io;
 	bus->resource[1] = &irongate_mem;
 
 	pci_bus_size_bridges(bus);