DisparityWLSFilterImpl ignores minimal disparity

[S1lverhand]

The current implementation of DisparityWLSFilterImpl seems to ignore the minimal disparity value. This is a snippet from the current code:

void DisparityWLSFilterImpl::init(double _lambda, double _sigma_color, bool _use_confidence,  int l_offs, int r_offs, int t_offs, int b_offs, int _min_disp)
{
    left_offset = l_offs; right_offset  = r_offs;
    top_offset  = t_offs; bottom_offset = b_offs;
    min_disp = _min_disp;
    valid_disp_ROI = Rect();
    right_view_valid_disp_ROI = Rect();
    min_disp=0;

min_disp is first set correctly, but then it is overwritten.

The change is 10 years old, but maybe @sbokov is still around to comment on this.