Customize the WCDMA signal strength based on RSCP

Determines the the display level of WCDMA signal bar based on RSCP
according to carrier config.

Test: manual - Checked that the WCDMA signal bar thresholds can be
controlled by carrier config.
Test: auto - Passed SignalStrengthTest and ServiceStateTrackerTest
Bug: 71329173
Change-Id: Ib9e1c29fbe3553d1cc6695953be1c33daf260627
2 files changed