vp9: 1 pass vbr: Small fix on reset avg_intersize_gfint on scene cut.

Change-Id: Ie73d1bbc2c953d010b32097440698f0d060750be
diff --git a/vp9/encoder/vp9_ratectrl.c b/vp9/encoder/vp9_ratectrl.c
index 59f508c..3bd1753 100644
--- a/vp9/encoder/vp9_ratectrl.c
+++ b/vp9/encoder/vp9_ratectrl.c
@@ -2126,6 +2126,7 @@
       target = calc_pframe_target_size_one_pass_vbr(cpi);
       vp9_rc_set_frame_target(cpi, target);
       rc->count_last_scene_change = 0;
+      rc->avg_intersize_gfint = 0;
     } else {
       rc->count_last_scene_change++;
     }