Hide actions and number in disconnect notification

When an emergency call is disconnected because another outgoing
emergency call was made, do not show the number called for privacy
reasons, and do not include the "call back" and "message" intents to
avoid pocket dials.

Fixes: 150278492
Test: atest TelecomUnitTests:DisconnectedCallNotifierTest
Test: manual
Change-Id: Id8585d05de1448f0aabc54aa0a848f5ff84ade7c