Cast allocated pointers to proper types.

Change-Id: I473135d28e1d7f16bd37652ffeaad62dfd9bbe73

ivfdec.c

@@ -76,7 +76,7 @@ int ivf_read_frame(FILE *infile, uint8_t **buffer, size_t *bytes_read,
     }
 
     if (frame_size > *buffer_size) {
-      uint8_t *new_buffer = realloc(*buffer, 2 * frame_size);
+      uint8_t *new_buffer = (uint8_t *)realloc(*buffer, 2 * frame_size);
 
       if (new_buffer) {
         *buffer = new_buffer;

video_reader.c

@@ -40,7 +40,7 @@ AvxVideoReader *aom_video_reader_open(const char *filename) {
 
   if (mem_get_le16(header + 4) != 0) return NULL;  // Wrong IVF version
 
-  reader = calloc(1, sizeof(*reader));
+  reader = (AvxVideoReader *)calloc(1, sizeof(*reader));
   if (!reader) return NULL;  // Can't allocate AvxVideoReader
 
   reader->file = file;