Move Sms API to proper MMTelFeature class

- while here remove unnecessary call to ackSms from
  SmsImplBase as this is handled by ImsSmsDispatcher

Test: None, APIs not exercised yet.
BUG=69846044
Merged-In: Iec4bbd07a67502dbbfb2142a7bc95f51be0cb377
Change-Id: Iec4bbd07a67502dbbfb2142a7bc95f51be0cb377
6 files changed