Fix nightly build issue for CONFIG_AV1_TEMPORAL_DENOISING

Fixed nightly build warning seen in fill_variance_tree_leaves()
for CONFIG_AV1_TEMPORAL_DENOISING.

Change-Id: If99262b31e33058e3ca492b3ac2742e5dc843a7b
diff --git a/av1/encoder/var_based_part.c b/av1/encoder/var_based_part.c
index 9abbf68..2adec67 100644
--- a/av1/encoder/var_based_part.c
+++ b/av1/encoder/var_based_part.c
@@ -1024,7 +1024,7 @@
   const int segment_id = xd->mi[0]->segment_id;
   int pixels_wide = 128, pixels_high = 128;
   int border_offset_4x4 = 0;
-  const bool temporal_denoising = cpi->sf.rt_sf.use_rtc_tf;
+  int temporal_denoising = cpi->sf.rt_sf.use_rtc_tf;
   if (is_small_sb) {
     pixels_wide = 64;
     pixels_high = 64;