Decoding the detailed meaning of the flags of SRv6-related TLV

## SRv6 End.X SID

- [x] 1. ISIS。Reference：[rfc9352#name-srv6-endx-sid-sub-tlv](https://datatracker.ietf.org/doc/html/rfc9352#name-srv6-endx-sid-sub-tlv)
- [x] 2. OSPFv3。Reference：[draft-ietf-lsr-ospfv3-srv6-extensions-09#section-9.1](https://datatracker.ietf.org/doc/html/draft-ietf-lsr-ospfv3-srv6-extensions-09#section-9.1)