aacenc: populate the sce->ics.swb_offset table pointer

This commit simply populates the table pointer which is needed
for upcoming commits (TNS, prediction, etc.). Copied from
the decoder.
Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>

libavcodec/aacenc.c

@@ -513,6 +513,9 @@ static int aac_encode_frame(AVCodecContext *avctx, AVPacket *avpkt,
             ics->num_windows        = wi[ch].num_windows;
             ics->swb_sizes          = s->psy.bands    [ics->num_windows == 8];
             ics->num_swb            = tag == TYPE_LFE ? ics->num_swb : s->psy.num_bands[ics->num_windows == 8];
+            ics->swb_offset         = wi[ch].window_type[0] == EIGHT_SHORT_SEQUENCE ?
+                                        ff_swb_offset_128 [s->samplerate_index]:
+                                        ff_swb_offset_1024[s->samplerate_index];
             clip_avoidance_factor = 0.0f;
             for (w = 0; w < ics->num_windows; w++)
                 ics->group_len[w] = wi[ch].grouping[w];