ASoC: msm: qdsp6v2: set proper channel mapping for ALAC format

Current channel mapping of multichannel ALAC clips is different
from the one the decoder expects due to which playback of
multichannel ALAC clips does not work in non-tunnel mode.

Set the pre-defined channel mapping according to the ALAC specification
for multichannel ALAC clips based on the number of channels for
decoding to succeed.

CRs-Fixed: 843138
Change-Id: I7c8b7cf8cc555b9667a1713d59999460e6251732
Signed-off-by: Satya Krishna Pindiproli <satyak@codeaurora.org>