msm: audio: qdsp5v2: Handle the VOICE_START event

Handle VOICE START event when voice state is in voice change
Consider the following case
B calls A (A accept the call), voice state in voice acquire
C calls A (A accept and B in hold) in this scenario following series
Of events issue to voice driver
VOICE_END (this event issues a device change command to modem, in turn
Modem changes the voice state from voice acquire to voice change)

VOICE_START (this event is not changing the voice state from voice change
To voice acquire as a result mismatch in the voice state maintained by
Voice proxy driver)

This patch change the voice state from voice change to voice acquire
When VOICE_START event received and voice state is in voice change

CRs-Fixed: 295375
Signed-off-by: Santosh Mardi <gsantosh@codeaurora.org>