avcodec/faxcompr: Fix memleak

Fixes CID1270816
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

libavcodec/faxcompr.c

@@ -297,7 +297,7 @@ int ff_ccitt_unpack(AVCodecContext *avctx, const uint8_t *src, int srcsize,
     ref[1] = 0;
     ref[2] = 0;
     if ((ret = init_get_bits8(&gb, src, srcsize)) < 0)
-        return ret;
+        goto fail;
     has_eol = show_bits(&gb, 12) == 1 || show_bits(&gb, 16) == 1;
 
     for (j = 0; j < height; j++) {