Add disconnect cause when outgoing call fails due to ongoing OTASP prov.

Adding a new disconnect cause shown to the user when they attempt to place
a call when OTASP provisioning is in process.

Test: Manual with test intent.
Test: Added unit test.
Bug: 70843686
Change-Id: Ia555408d22d6b3de12511da0584eea2f175252cd
4 files changed