avcodec/flashsv: fix typo

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

libavcodec/flashsv.c

@@ -255,7 +255,7 @@ static int flashsv_decode_frame(AVCodecContext *avctx, void *data,
     if (buf_size < 4)
         return -1;
 
-    if ((ret = init_get_bits(&gb, avpkt->data, buf_size)) < 0)
+    if ((ret = init_get_bits8(&gb, avpkt->data, buf_size)) < 0)
         return ret;
 
     /* start to parse the bitstream */