Add support to retry for DDS switch failures

DDS requests are rejected when there is active call. Add support
to retry failed DDS switch imediately on call end

Also, DDS request fails when SIM is not ready. Retry failed DDS
switch once SIM moves to ready state

Added UT for these changes

Change-Id: I34021984b0245d53ccce80dd986434ff1539f645
Bug: 169649103
Test: Unit tests