lavfi/noise: add missing emms_c()

Signed-off-by: Paul B Mahol <onemda@gmail.com>

libavfilter/vf_noise.c

@@ -393,6 +393,7 @@ static int filter_frame(AVFilterLink *inlink, AVFrame *inpicref)
     for (i = 0; i < n->nb_planes; i++)
         noise(out->data[i], inpicref->data[i], out->linesize[i],
               inpicref->linesize[i], n->linesize[i], n->height[i], n, i);
+    emms_c();
 
     if (inpicref != out)
         av_frame_free(&inpicref);