Fix an IOC

Change-Id: I0ca6746696d81657c035b0f6523c9af370da3c95

vp9/encoder/vp9_rdopt.c

@@ -2585,7 +2585,7 @@ int64_t vp9_rd_pick_inter_mode_sb(VP9_COMP *cpi, MACROBLOCK *x,
   int mode_skip_start = cpi->sf.mode_skip_start + 1;
   const int *const rd_threshes = rd_opt->threshes[segment_id][bsize];
   const int *const rd_thresh_freq_fact = rd_opt->thresh_freq_fact[bsize];
-  int mode_threshold[MAX_MODES];
+  int64_t mode_threshold[MAX_MODES];
   int *mode_map = rd_opt->mode_map[bsize];
   const int mode_search_skip_flags = cpi->sf.mode_search_skip_flags;
   vp9_zero(best_mbmode);