aacenc: Finish 3GPP psymodel analysis for non mid/side cases.

There is still are still a few sections missing relating to TNS (not present)
and mid/side (contains other bugs).

Overall this improves quality, and vastly improves rate-control.
Signed-off-by: Martin Storsjö <martin@martin.st>

libavcodec/aacenc.c

@@ -606,8 +606,10 @@ static int aac_encode_frame(AVCodecContext *avctx,
         }
 
         frame_bits = put_bits_count(&s->pb);
-        if (frame_bits <= 6144 * avctx->channels - 3)
+        if (frame_bits <= 6144 * avctx->channels - 3) {
+            s->psy.bitres.bits = frame_bits / avctx->channels;
             break;
+        }
 
         s->lambda *= avctx->bit_rate * 1024.0f / avctx->sample_rate / frame_bits;