avfilter/vf_colorconstancy: fix memory leak on error

Also remove unneeded log message while here.

libavfilter/vf_colorconstancy.c

@@ -121,7 +121,6 @@ static int set_gauss(AVFilterContext *ctx)
             for (; i >= 0; --i) {
                 av_freep(&s->gauss[i]);
             }
-            av_log(ctx, AV_LOG_ERROR, "Out of memory while allocating gauss buffers.\n");
             return AVERROR(ENOMEM);
         }
     }
@@ -223,7 +222,6 @@ static int setup_derivative_buffers(AVFilterContext* ctx, ThreadData *td)
             td->data[b][p] = av_mallocz_array(s->planeheight[p] * s->planewidth[p], sizeof(*td->data[b][p]));
             if (!td->data[b][p]) {
                 cleanup_derivative_buffers(td, b + 1, p);
-                av_log(ctx, AV_LOG_ERROR, "Out of memory while allocating derivatives buffers.\n");
                 return AVERROR(ENOMEM);
             }
         }
@@ -696,7 +694,7 @@ static int filter_frame(AVFilterLink *inlink, AVFrame *in)
     } else {
         out = ff_get_video_buffer(outlink, outlink->w, outlink->h);
         if (!out) {
-            av_log(ctx, AV_LOG_ERROR, "Out of memory while allocating output video buffer.\n");
+            av_frame_free(&in);
             return AVERROR(ENOMEM);
         }
         av_frame_copy_props(out, in);