turn off parallelization of step 4 of rcd

as the arrays are read and written, doing parallel operations properly requires some deeper analysis of the code. For now, let's simply disable them. We can always optimize later

rtengine/demosaic_algos.cc

@@ -4122,9 +4122,6 @@ void RawImageSource::rcd_demosaic()
     /**
     * STEP 4: Populate the red and blue channel
     */
-#ifdef _OPENMP
-    #pragma omp parallel for
-#endif
     for ( int row = 4; row < height - 4; row++ ) {
         for ( int col = 4 + ( FC( row, 0 )&1 ), indx = row * width + col, c = 2 - FC( row, col ); col < width - 4; col += 2, indx += 2 ) {
 
@@ -4155,9 +4152,6 @@ void RawImageSource::rcd_demosaic()
     }
     // -------------------------------------------------------------------------
     
-#ifdef _OPENMP
-    #pragma omp parallel for
-#endif
     for ( int row = 4; row < height - 4; row++ ) {
         for ( int col = 4 + ( FC( row, 1 )&1 ), indx = row * width + col; col < width - 4; col += 2, indx += 2 ) {