vp8 denoiser fix: free memory of denoiser->denoiser_state.

Change-Id: I86451ddfa90d871e46e5b4c97794dbef65293c6c

vp8/encoder/denoising.c

@@ -383,6 +383,7 @@ void vp8_denoiser_free(VP8_DENOISER *denoiser)
         vp8_yv12_de_alloc_frame_buffer(&denoiser->yv12_running_avg[i]);
     }
     vp8_yv12_de_alloc_frame_buffer(&denoiser->yv12_mc_running_avg);
+    vpx_free(denoiser->denoise_state);
 }