Add wsa2 backend dai links only in platforms
which has 4 wsa speakers.
add 2 to the device index parsed from hardware device id
of wsa slave to match the dai names in the msm_dailink.h
Change-Id: Iffe43842123526f4925f9d5bcd8dff0317bac7a7
Signed-off-by: Junkai Cai <junkai@codeaurora.org>