resource: add bus number support

Add support for bus number resources.  This is for bridges with a range of
bus numbers behind them.

Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
diff --git a/include/linux/ioport.h b/include/linux/ioport.h
index b126209..510e4ac 100644
--- a/include/linux/ioport.h
+++ b/include/linux/ioport.h
@@ -39,6 +39,7 @@
 #define IORESOURCE_MEM		0x00000200
 #define IORESOURCE_IRQ		0x00000400
 #define IORESOURCE_DMA		0x00000800
+#define IORESOURCE_BUS		0x00001000
 
 #define IORESOURCE_PREFETCH	0x00002000	/* No side effects */
 #define IORESOURCE_READONLY	0x00004000