MSIM(DSDA): Remain in LCH if call on other sub is ended remotely

- Add deactivateLchState to deactivate sub's LCH state
- When call on the current active sub is ended remotely, and the other
  sub is currently in LCH state, do NOT deactivate the LCH state. Do so
  only when deactivateLchState is called.

Change-Id: I04f91023a97e8d869aed7b7ca0bfa3bfb6bb6948
CRs-Fixed: 548848