fix ipv6 flag order in worlddump

this change corrects the flag order from 'route -6'
to '-6 route' as the -6 flag is an option when used with
ip is an argument to the the ip command and not the route
subcommand.

-6 is accpeted as an argument to the standalone 'route'
commannd but not 'ip route' subcommand.

Change-Id: Ic2ae472e42b7b455693d0aade48dc5109e1f21ba

Author: SeanMooney

tools/worlddump.py

@@ -165,7 +165,7 @@ def network_dump():
 
     _dump_cmd("bridge link")
     _dump_cmd("ip link show type bridge")
-    ip_cmds = ["neigh", "addr", "route", "route -6"]
+    ip_cmds = ["neigh", "addr", "route", "-6 route"]
     for cmd in ip_cmds + ['netns']:
         _dump_cmd("ip %s" % cmd)
     for netns_ in _netns_list():