Support the following new features in srv6-mobile.
1. GTP4.DT
2. GTP6.DT
3. User Plane Message encoding based on draft-murakami-dmm-user-plane-message-encoding-01
4. Add SRv6 mobile test cases
Type: feature
Signed-off-by: Tetsuya Murakami <tetsuya.mrk@gmail.com>
Change-Id: I890e5171bf03513d54b4830f01b9dc7f47fe7c48
Signed-off-by: Tetsuya Murakami <tetsuya.mrk@gmail.com>