avcodec/tscc2: use init_get_bits8()

Signed-off-by: Paul B Mahol <onemda@gmail.com>

libavcodec/tscc2.c

@@ -192,7 +192,8 @@ static int tscc2_decode_slice(TSCC2Context *c, int mb_y,
     int i, mb_x, q, ret;
     int off;
 
-    init_get_bits(&c->gb, buf, buf_size * 8);
+    if ((ret = init_get_bits8(&c->gb, buf, buf_size)) < 0)
+        return ret;
 
     for (mb_x = 0; mb_x < c->mb_width; mb_x++) {
         q = c->slice_quants[mb_x + c->mb_width * mb_y];