Fix static analysis warnings

With this change the number of warnings of shallow analysis is 0 and of
deep analysis is 9. 5 of those 9 are in third_party and the other 4 are
due to pointer conversion

Change-Id: Ibd94f867f429024a7b4e2dbce05223a263994a24
diff --git a/aom_dsp/noise_model.c b/aom_dsp/noise_model.c
index 7e6a833..528efd9 100644
--- a/aom_dsp/noise_model.c
+++ b/aom_dsp/noise_model.c
@@ -214,6 +214,7 @@
 
 int aom_noise_strength_lut_init(aom_noise_strength_lut_t *lut, int num_points) {
   if (!lut) return 0;
+  lut->num_points = 0;
   lut->points = (double(*)[2])aom_malloc(num_points * sizeof(*lut->points));
   if (!lut->points) return 0;
   lut->num_points = num_points;