macvlan: fix typo in macvlan_print_opt()

The mode information is contained in IFLA_MACVLAN_MODE instead
of IFLA_VLAN_ID (both evaluating to "1" in their enums).

Signed-off-by: Lutz Jaenicke <ljaenicke@innominate.com>
diff --git a/ip/iplink_macvlan.c b/ip/iplink_macvlan.c
index 5b4b868..ec51106 100644
--- a/ip/iplink_macvlan.c
+++ b/ip/iplink_macvlan.c
@@ -79,7 +79,7 @@
 	    RTA_PAYLOAD(tb[IFLA_MACVLAN_MODE]) < sizeof(__u32))
 		return;
 
-	mode = rta_getattr_u32(tb[IFLA_VLAN_ID]);
+	mode = rta_getattr_u32(tb[IFLA_MACVLAN_MODE]);
 	fprintf(f, " mode %s ",
 		  mode == MACVLAN_MODE_PRIVATE ? "private"
 		: mode == MACVLAN_MODE_VEPA    ? "vepa"