Fix RatRatcheter skipping the first Ratchet

The code was skipping the first ratchet, which is the second
time that RatRatcheter#ratchet() was being called on the same
cell. This CL:
-fixes the bug that was causing the first ratchet to be skipped;
-simplifies the logic so that the ratcheter is only called
 when ratcheting should be performed, moving the check for
 whether or not to ratchet back into SST;
-ratchets if the registered cell is a voice or data registration
 which fixes a bug that CS-only registrations (such as on WCDMA)
 weren't being ratcheted.

Bug: 156676862
Test: atest RatRatcheterTest; atest ServiceStateTrackerTest
Change-Id: I710c338289d54d2029dc5aba572ba201d07872af