SRH has passed WG review in IETF and currently an IESG document.
This patch updates the SRH definition to be compliant with IETF.
- Change "first_segment" to "last_entry"
- Change "reserved" to "tag"
Change-Id: I1765c968671655c5646f6de478d1f7196abbc040
Type: fix Signed-off-by: Ahmed Abdelsalam <ahabdels@cisco.com>