Fix to load CarrierConfig after SUB is generated

- Currently CarrierConfig does not wait SUB READY
  to broadcast ACTION_CARRIER_CONFIG_CHANGED

- ImsPhoneCallTracker might get dummy SUB id that
  skips updating the cache

- Fix by waiting for SUB id to be generated before
  loading CarrierConfig

Bug: 112870294
Test: Manual test and Telephony unit sanity test

Change-Id: I62a30abed37d7b64c97111b84ab11e1cc531ae90