avcodec/libaomdec: remove bogus comment

It's a remnant from libvpx that's not valid for libaom.
Signed-off-by: James Almer <jamrial@gmail.com>

libavcodec/libaomdec.c

@@ -42,7 +42,6 @@ static av_cold int aom_init(AVCodecContext *avctx,
 {
     AV1DecodeContext *ctx           = avctx->priv_data;
     struct aom_codec_dec_cfg deccfg = {
-        /* token partitions+1 would be a decent choice */
         .threads = FFMIN(avctx->thread_count ? avctx->thread_count : av_cpu_count(), 16)
     };