net_list: Add acl test cases for net-list command

By default the access for network api 'read' and 'getattr' is granted
for unprivileged user, add test case for testing this.

Signed-off-by: Wayne Sun <gsun@redhat.com>
net_dumpxml: Add acl test cases for net-dumpxml command

By default the access for network api 'read' and 'getattr' is granted
for unprivileged user, add test case for testing this via net-dumpxml.

Signed-off-by: Wayne Sun <gsun@redhat.com>