[non-BE] Fix ParamUpmix covariance smoothing
Covariance smoothing change FIX_331_ALL_BRS caused audio quality degradation in ParamUpmix. I will revert the change in the case of multichannel operation.
Edited by PLAINSI
Covariance smoothing change FIX_331_ALL_BRS caused audio quality degradation in ParamUpmix. I will revert the change in the case of multichannel operation.