Added getActiveSubInfoCount

Added getActiveSubInfoCount and migrated more modules
to use SubscrtipionManagerService.

Test: atest FrameworksTelephonyTests
Bug: 239607619
Merged-In: I114f28b781c5f09e26fed1b4af8002ff53fb2458
Change-Id: I114f28b781c5f09e26fed1b4af8002ff53fb2458
3 files changed