Support multiple RANs in one request for setSignalStrengthReportingCriteria

- Move AccessNetwork (RAN) into SignalThresholdInfo to be better organized
- Support specifying multiple RANs and measurement types in one request

Bug: 200055871
Test: m -j
Merged-In: Ic6762e8ca488a119b1103319e7443c4342530f8c
Change-Id: Ic6762e8ca488a119b1103319e7443c4342530f8c
(cherry picked from commit 9073f557)