The reserved implicit-NULL label isn't allowed to appear in the label
stack for packets, so make it an error for the control plane to
specify it as an outgoing label.
Suggested-by: N"Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: NRobert Shearman <rshearma@brocade.com>
Reviewed-by: N"Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>