x86/pci: Add cap_resource()

Prepare for 32bit pci root bus

-v2: hpa said we should compare with (resource_size_t)~0
-v3: according to Linus to use MAX_RESOURCE instead.
     also need need to put related patches together
-v4: according to Andrew, use min in cap_resource()

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <1265793639-15071-8-git-send-email-yinghai@kernel.org>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>

arch/x86/pci/bus_numa.c

@@ -1,5 +1,6 @@
 #include <linux/init.h>
 #include <linux/pci.h>
+#include <linux/range.h>
 
 #include "bus_numa.h"
 
@@ -55,6 +56,9 @@ void __devinit update_res(struct pci_root_info *info, resource_size_t start,
 	if (start > end)
 		return;
 
+	if (start == MAX_RESOURCE)
+		return;
+
 	if (!merge)
 		goto addit;