Frameworks: Annotate trivial @GuardedBy in services/core

Add @GuardedBy for simple functions that require locks and have a name in
one of the frameworks naming styles for locks ("^.*(Locked|LPw|LPr|L[a-zA-Z]|UL|AL|NL)$").

Changelist for network manager.

Derived by errorprone.

Bug: 73000847
Test: m
Change-Id: Ie2e0c239a6e59d934a2db4f9f3efdde177e8a4de