Rename tunnel mode local/remote addresses to src/dst

Update tunnel mode addresses to more correctly reflect their usage.
These addresses are used for matching SAs, which should be denoted as
source/destination pairs instead of local or remote.

Bug: 79384676
Test: Tests passing (integration + unit tests)
Change-Id: I2bbc3bb5add11155d83475c61a9dcea7be26bf0b
5 files changed