ocl: correct disabling of OpenCL code

modules/video/src/lkpyramid.cpp

@@ -837,6 +837,7 @@ int cv::buildOpticalFlowPyramid(InputArray _img, OutputArrayOfArrays pyramid, Si
     return maxLevel;
 }
 
+#ifdef HAVE_OPENCL
 namespace cv
 {
     class PyrLKOpticalFlow
@@ -1084,6 +1085,7 @@ namespace cv
         return opticalFlow.sparse(_prevImg.getUMat(), _nextImg.getUMat(), _prevPts.getUMat(), umatNextPts, umatStatus, umatErr);
     }
 };
+#endif
 
 void cv::calcOpticalFlowPyrLK( InputArray _prevImg, InputArray _nextImg,
                            InputArray _prevPts, InputOutputArray _nextPts,
@@ -1092,6 +1094,7 @@ void cv::calcOpticalFlowPyrLK( InputArray _prevImg, InputArray _nextImg,
                            TermCriteria criteria,
                            int flags, double minEigThreshold )
 {
+#ifdef HAVE_OPENCL
     bool use_opencl = ocl::useOpenCL() &&
                       (_prevImg.isUMat() || _nextImg.isUMat()) &&
                       ocl::Image2D::isFormatSupported(CV_32F, 1, false);
@@ -1100,6 +1103,7 @@ void cv::calcOpticalFlowPyrLK( InputArray _prevImg, InputArray _nextImg,
         CV_IMPL_ADD(CV_IMPL_OCL);
         return;
     }
+#endif
 
     Mat prevPtsMat = _prevPts.getMat();
     const int derivDepth = DataType<cv::detail::deriv_type>::depth;