BT-HF: Set correct callState for MT/MO call while in Voip Call.

Specific handling for case of starting MO/MT call while VOIP
is ongoing, terminateScoUsingVirtualVoiceCall() resets callState
from INCOMING/DIALING to IDLE. Some HS send AT+CIND? to read call
indicators and get wrong value of callsetup. This case is hit only
when SCO for VOIP call is not terminated via SDK API call.

Change-Id: I5e529c984a2cc8c68e539451a78712167523e5eb
CRs-Fixed: 710598