avcodec/mjpegdec: Remove redundant initialization

Now that the correct number of codes is used, it is no longer necessary
to initialize the lengths of the codes at all any more as the length of
the actually used codes is set later anyway.

Reviewed-by: Paul B Mahol <onemda@gmail.com>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>

libavcodec/mjpegdec.c

@@ -69,7 +69,7 @@ static int build_vlc(VLC *vlc, const uint8_t *bits_table,
                      const uint8_t *val_table, int nb_codes,
                      int is_ac)
 {
-    uint8_t huff_size[256] = { 0 };
+    uint8_t huff_size[256];
     uint16_t huff_code[256];
     uint16_t huff_sym[256];
     int i;