Fix compiler warning of out-of-bound array access

Change-Id: I00f147cd372cedc5038708b0f23f6fae68918528

av1/encoder/pvq_encoder.c

diff --git a/av1/encoder/pvq_encoder.c b/av1/encoder/pvq_encoder.c
index 611f0b6..6143fe8 100644
--- a/av1/encoder/pvq_encoder.c
+++ b/av1/encoder/pvq_encoder.c
@@ -912,7 +912,8 @@
       int j;
       int tmp;
       tmp = 1;
-      for (j = i + 1; j < nb_bands; j += 3) {
+      // ToDo(yaowu): figure out better stop condition without gcc warning.
+      for (j = i + 1; j < nb_bands && j < PVQ_MAX_PARTITIONS; j += 3) {
         if (theta[j] != skip_theta_value || qg[j]) tmp = 0;
       }
       skip_dir |= tmp << i;