ASoC: msm: qdsp6v2: add FM volume support for Quat MI2S

APQ8084 uses Quaternary MI2S port for connecting a FM
chip. Add routes for FM device volume control using MI2S
AFE loopback path.

Change-Id: I1ec22efdf7054f524bf8f72f165bd09cb7af45cd
Signed-off-by: Banajit Goswami <bgoswami@codeaurora.org>