powerpc/pseries/pci: Use NULL instead of 0 for pointers

The third argument for of_get_property() is a pointer, hence pass
NULL instead of 0.

Signed-off-by: Tushar Behera <tushar.behera@linaro.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
diff --git a/arch/powerpc/platforms/pseries/pci.c b/arch/powerpc/platforms/pseries/pci.c
index 56b864d..0b580f4 100644
--- a/arch/powerpc/platforms/pseries/pci.c
+++ b/arch/powerpc/platforms/pseries/pci.c
@@ -40,7 +40,8 @@
 	 */
 	dn = pci_device_to_OF_node(dev);
 	if (dn) {
-		const char *loc_code = of_get_property(dn, "ibm,loc-code", 0);
+		const char *loc_code = of_get_property(dn, "ibm,loc-code",
+				NULL);
 		if (loc_code) {
 			int loc_len = strlen(loc_code);
 			if (loc_len < sizeof(dev->dev.name)) {