ASoC: msm: qdsp6v2: Add routing commands to support voice2 call

Add mixer commands to route voice2 call to proper backend dais
to support DSDS/DSDA for APQ+MDM target.

Change-Id: I80ba389757734a3a75a4c6e1f341ac90107f8f5b
Signed-off-by: Helen Zeng <xiaoyunz@codeaurora.org>