audio: Inform audio HAL if it is a voice call initiated by Telephony

setMode() API with IN_CALL mode can be called by any of the Apps.
In HAL, it is required to distinguish if it is a real voice call
or not. Inform to audio HAL if it is a voice call by checking
getPhonestate() updated by telephony.

Change-Id: I20a661f49f6566bdd1e23d6de18b509e2728ef19