Draft: Few functions in ivas_mct_dec_mct converted to fixed point.
Added changes for the following functions:
[x] indexToChannelPair()
[x] ivas_mct_dec_mct()
[x] applyGlobalILD()
[x] apply_MCT_dec()
[x] stereo_decoder_tcx()
Added changes for the following functions:
[x] indexToChannelPair()
[x] ivas_mct_dec_mct()
[x] applyGlobalILD()
[x] apply_MCT_dec()
[x] stereo_decoder_tcx()