voice_svc: Avoid double free in voice_svc driver

voice_svc_dev is allocated as a device managed resource
and need not be freed since it is freed automatically.
Remove the logic to free voice_svc_dev in probe failure
and remove functions to avoid double free.

CRs-Fixed: 2204285
Change-Id: If4f9ca840b00448b987f5ce443f66b0923b01969
Signed-off-by: Aditya Bavanari <abavanar@codeaurora.org>