Added implementation for VTI add/remove address

This change adds implementation details for add/remove addresses onto a
VTI.

Bug: 73675031
Test: New tests added, passing on Walleye
Merged-In: Idde9d943a5285d2c13c5c6b0f7b8a9faf718e6a5
Change-Id: Idde9d943a5285d2c13c5c6b0f7b8a9faf718e6a5
(cherry picked from commit ecc9f7cc08804e3fa15fea04ae94ea1bc74edbfe)
5 files changed