Fix build error caused by a merge conflict.

Commit 70d9664f removed 'int i' required by a4f30a50.

Change-Id: I4e7e14e9e8532f753e43a57b5bba4589d58e0c32

vpxdec.c

@@ -482,6 +482,7 @@ static FILE *open_outfile(const char *name) {
 int main_loop(int argc, const char **argv_) {
   vpx_codec_ctx_t       decoder;
   char                  *fn = NULL;
+  int                    i;
   uint8_t               *buf = NULL;
   size_t                 bytes_in_buffer = 0, buffer_size = 0;
   FILE                  *infile;