ASoC: wcdxxxx: Add check for buffer overflow

Current code does not check if the indexes of array
codec_dai being accessed is within the maximum
number of codec dais for a particular codec. The change
adds this check and ensures that indexes outside the
bounds of array are not accessed.

CRs-Fixed: 628865
Change-Id: Ibf81f91b35e43feddc6b03a1239b4d12e04a95da
Signed-off-by: Aravind Kumar <akumark@codeaurora.org>