Bugfix related to qindex for KF min/max dist of 0

When "--kf-min-dist=0 --kf-max-dist=0" is given, base_qindex of all the
frames should be same as the provided cq_level.

Earlier, 1st frame was incorrectly using a lower qindex.

BUG=aomedia:2725

Change-Id: Ib5f4aee95a8dfe618503108f2853b6898e5b1b50
(cherry picked from commit 8db5ca98460ae4843e657ef53abd26632d6ce07f)

av1/encoder/ratectrl.c

diff --git a/av1/encoder/ratectrl.c b/av1/encoder/ratectrl.c
index 433163f..3079e98 100644
--- a/av1/encoder/ratectrl.c
+++ b/av1/encoder/ratectrl.c
@@ -907,7 +907,7 @@
 
   int offset_idx = -1;
   if (update_type == KF_UPDATE) {
-    if (rc->frames_to_key == 1) {
+    if (rc->frames_to_key <= 1) {
       // Image / intra-only coding: ignore offsets.
       return cq_level;
     }
@@ -1146,7 +1146,7 @@
   int active_worst_quality = *active_worst;
   const int bit_depth = cm->seq_params.bit_depth;
 
-  if (rc->frames_to_key == 1 && oxcf->rc_mode == AOM_Q) {
+  if (rc->frames_to_key <= 1 && oxcf->rc_mode == AOM_Q) {
     // If the next frame is also a key frame or the current frame is the
     // only frame in the sequence in AOM_Q mode, just use the cq_level
     // as q.