OSPFv3-TTL propagation policy for TE-Shortcuts and FA-LSPs in-line with other modules in the system

The OSPFv3-TTL propagation policy will be dictated by MPLS-TTL propagation policy which, by default, allows propagation of TTL. This change makes behavior of OSPFV3 in-line with the default behavior of rest of the system, allowing you to disable TTL propagation for the above mentioned LSPs and for traffic-engineering-shortcuts (TE-Shortcuts) and forwarding adjacency LSPs (FA-LSPs) using OSPFv3 as IGP, by configuring the no-propagate-ttl statement at the [edit protocols mpls] hierarchy.