Fix missing bs_flush in AUD writing

encoder/encoder.c

@@ -3499,6 +3499,7 @@ int     x264_encoder_encode( x264_t *h,
         nal_start( h, NAL_AUD, NAL_PRIORITY_DISPOSABLE );
         bs_write( &h->out.bs, 3, pic_type );
         bs_rbsp_trailing( &h->out.bs );
+        bs_flush( &h->out.bs );
         if( nal_end( h ) )
             return -1;
         overhead += h->out.nal[h->out.i_nal-1].i_payload + NALU_OVERHEAD;