audio: fix device pair for VOIP case

Since the dedicated VOIP output has been enabled, to select
VOIP device pair by primary output may not be solid.

To check the voip output first in VOIP case in case the wrong output device
is passed to get_snd_input_device function.

Bug: 64774724
Test: manual audio test
Change-Id: If7efbb40fe28d1b9ac1435406b2693cfb3be8ed8
Signed-off-by: carter_hsu <carter_hsu@htc.com>